Prosauropod dinosaurs

The Prosauropods, also known as Plateosaurids, were the first large dinosaurs. They lived during the late Triassic and early Jurassic eras (230-180 million years ago).

They were plant-eating dinosaurs with long necks and tails, small heads, wide bodies and four strong legs. Although they walked on all fours, some of them, such as Plateosaurus, may have reared up on their hind legs to reach leaves on tall plants. This was an animal that was up to nine metres long and may have weighed as much as three tonnes.

Riojasaurus lived about 220-215 million years ago in what is now Argentina. It was ten metres long and probably weighed about two tonnes.

Fossils of Sellosaurus, which lived 215-210 million years ago, have been found in Europe.

Lufengosaurus, from the early Jurassic, lived in what is now China and was up to nine metres long. A skeleton of Lufengosaurus was the first complete dinosaur fossil to be found in that country.

The Prosauropods were followed by the Sauropods that were even bigger but with the same basic shape having long necks and tails.

© John Welford

Baryonyx

Baryonyx was a carnivorous dinosaur that lived in the early Cretaceous era about 130 million years ago. The first discovery of a Baryonyx fossil was made in Surrey, England, in 1983.

Baryonyx was about 10 metres long, of slim shape, with a long narrow tail and a crocodile-like mouth and snout. An unusual feature was the strong thumb claw on the front legs. This claw measured 35 centimetres in length and may well have been related to Baronyx’s feeding habits.

Specimens of Baronyx have been found alongside fossilised fish scales, which give another clue as to this animal’s probable way of life.

It very much looks as though Baryonyx was a fish-eating dinosaur that behaved in a similar fashion to the modern crocodile. The signs point to Baryonyx having lived in swamps or alongside rivers. It would dart its long neck forward to snatch fish out of the water, and it would use its massive thumb claws to hook fish and other water-dwelling creatures.

Modern fresh-water crocodiles had not evolved during the era when Baryonyx was around, so it is entirely possible that Baryonyx was unchallenged in its role as a fish-eating predator at this time.

© John Welford

Eustreptospondylus

Eustreptospondylus was a large meat-eating dinosaur that lived during the Jurassic era about 165-160 million years ago. Its fossils have been found in an area that comprises the present-day counties of Oxfordshire and Buckinghamshire in England.

The first fairly complete specimen was found in 1870 and it was mistakenly categorised as “Megalosaurus”, which was the only genus of meat-eating dinosaurs known at the time to have existed in that region. It was not until 1964 that Eustreptospondylus was identified as a separate species and given its own name.

The name means “well-curved backbone”, which refers to the arrangement of the bones of the spine.

Eustreptospondylus measured about six metres from nose to tip of tail and probably weighed about 400 kilograms (900 pounds). It was equipped with a mouthful of very sharp teeth and would have been a fearsome hunter. It probably preyed on sauropod plant-eating dinosaurs such as Cetiosaurus.

© John Welford

Dilophosaurus

Dilophosaurus was a meat-eating therapod dinosaur that lived about 195-190 million years ago, which was in the early Jurassic period. It was one of the earliest large predatory dinosaurs that is known about from the fossil evidence.

Dilophosaurus was about six or seven metres in length, including its long tail. It probably weighed in excess of 500 kilograms (1100 pounds) which places it in the same weight category as the polar bear.

The name means “two ridged reptile”, which refers to the parallel plate-like ridges on the animal’s head. Given that these do not look to have been strong enough to be used as weapons, it is possible that they were covered in brightly coloured skin and used to warn off rivals or enemies, or as part of a mating ritual.

Fossils of dilophosaurus were found in 1942 in Arizona, USA, but the creatures may well have lived in other places. The species was only designated and named in 1970, due to difficulties posed by the fragmented nature of the fossils.

© John Welford

Coelophysis

Coelophysis was a small, agile dinosaur that lived during the Triassic era about 210 million years ago. It was about three metres long and it would have stood about waist-high to the average human, had any been around at the time. Being of light build, with hollow bones, it would only have weighed about 20 kilograms (44 pounds).

It had long, powerful back legs, so it would have been able to run quickly, and its smaller front legs would have been used like arms. It had “hands” with three clawed fingers that would have been used to catch and hold its prey. Its mouth was full of small sharp teeth.

The “arms” feature contrasts sharply with meat-eaters that appeared much later in the Dinosaur Age, such as Tyrannosaurus, that had forelimbs with no discernible purpose. More than 140 million years elapsed between Coelophysis and Tyrannosaurus, which is many millions of years longer than the gap between Tyrannosaurus and us! There was therefore plenty of time in which evolution could make substantial changes between dinosaurs similar to Coelophysis and those resembling Tyrannosaurus.

Coelophysis belonged to the therapod group of meat-eating dinosaurs. Its food probably consisted mainly of lizards, worms and insects.

A large number of Coelophysis fossils were found at Ghost Ranch, New Mexico, USA, in 1940. They may have been a herd of animals that drowned during a sudden flash flood.

© John Welford

Allosaurus

Ask just about anyone to name a meat-eating dinosaur and they are quite likely to say “Tyrannosaurus”. This was a fearsome hunter that lived at the end of the Age of the Dinosaurs about 65 million years ago. However, there was a very similar animal that filled the same niche in the natural world 90 million years earlier; this was Allosaurus.

Allosaurus lived during the late Jurassic about 155-150 million years ago. Fossils have found in the American midwest, notably Utah, Wyoming and Colorado. However, close relatives of Allosaurus may have lived in what is now Europe and Africa.

Allosaurus was 11-12 metres in length (36-39 feet) and could have weighed up to four tons. It had a massive head (up to a metre long) and jaws that could be flexed to allow huge bites to be taken.

The late Jurassic was also populated by massive sauropod dinosaurs including Diplodocus and Brachiosaurus. These may well have formed a major part of the diet of Allosaurus.

© John Welford

Common water-crowfoot

There are nine varieties of water-crowfoot found in the British Isles, and they are easily confused with each other. Their common features are that they are “water buttercups” and that, in most cases, they have two sets of leaves, one of which grows above the surface and the other below.

Common water-crowfoot (Ranunculus aquatilis) grows in ponds, streams and ditches throughout Great Britain, being absent only from highland areas. It has round leaves floating on the surface and feathery ones underneath. There may also be leaves that are transitional, in that they are sometimes above and sometimes below the surface.

The flowers, which are half an inch across, are white with a yellow centre. The globe-shaped fruiting bodies are carried on curving stalks that bend back towards the water. The flowers appear in May and June and often form impressive displays several feet across.

© John Welford

Common St John’s-wort

Common St John’s-wort (Hypericum perforatum) grows throughout Britain on grasslands and also next to hedges and in open woods, having a preference for chalky soils.

It throws up hairless erect stems that are woody at the base. This variety of St John’s-wort can be identified by the two narrow ribs that run up the stems on opposite sides. The small leaves are noticeable for appearing to be punctured if seen against the light (hence “perforatum”), although these are tiny translucent glands.

The flowers, which appear from June to September, are an inch across and have five widely-spaced yellow petals that have black dots on the edges. The stamens are in three bundles, which correspond to the three cells that are apparent in the seed capsule when it forms.

Common St John’s-wort was used extensively in medieval times as a medicinal plant. It was a stipulation of medieval herbal medicine that if a plant resembled a part of the human body then it had been made that way by God because it would cure diseases and injuries of that part. No part of common St John’s-wort has this correspondence, but the “punctures” on the leaves were thought to symbolise wounds, so the plant found a use in treating wounds, particularly if received in battle.

The name of the plant derives from this use, because it was part of the medical kit of the Knights of St John of Jerusalem during the Crusades.

Common St John’s-wort was also believed to have the power to drive away evil spirits. People would hang bunches of it over their doorway to keep the Devil at bay. If somebody believed that they had been possessed by a devil they would try prayer as their first resort but St John’s-wort as their second, wearing it on their person or strewing their cottage floor with it. 

© John Welford

Common scurvygrass

Common scurvygrass (Cochlearia officinalis) is a plant that grows around the British Isles on cliffs, seashores and in salt marshes, but only rarely inland. Despite its name it is not a grass but a member of the cabbage family.

The plant is hairless, throwing up long-stalked fleshy leaves that are shaped like hearts or kidneys. The lower leaves form a loose rosette. The plant grows to 20 inches (50 centimetres) in height.

The small white or lilac flowers appear from May to August. The seed-pods are globe-shaped.

Although the “grass” part of the name is a misnomer, the “scurvy” part is very relevant. The leaves are an excellent source of vitamin C and therefore offer protection against scurvy, which was a disease that afflicted sailors in past centuries whose food consisted almost entirely of salt pork and dried biscuits. When ashore, sailors would gather large quantities of scurvygrass from the surrounding area.

The plant was also used by non-sailors, given that outbreaks of scurvy could occur anywhere when fresh fruit and vegetables were not available, especially in winter. People in the 17th century would take a glass of “scurvygrass water” every morning, and a more appetising variant was a beer called “scurvygrass ale”.

© John Welford

Common poppy

The common poppy (Papaver rhoeas) is a familiar sight throughout the British Isles (except northern Scotland) with its bright red flowers that appear on many roadside verges and on the edges of cornfields. It may therefore be surprising to learn that the petals drop after only one day, but this is hardly noticeable given that a single plant can produce more than 400 flowers between May and October.

The common poppy is a tall, upright plant that can grow to 24 inches high (60 centimetres). The lower leaves are stalked and have narrow lobes and bristles at the tips, whereas the upper leaves, with their three lobes, are stalkless.

The flowers are 3-4 inches across (7.5-10 centimetres) with overlapping petals. The seed capsules are rounded with a ring of pores near the top from which the seeds are shaken when the wind blows.

Another name for the common poppy is the corn rose, which relates to its association with cornfields and the fact that it used to be seen much more commonly growing alongside corn in the days before selective weedkillers.

The use of the poppy as a symbol of remembrance dates from World War I when it was one of the few plants that would grow on the devastated fields of Flanders after they had been shelled and fought over.

© John Welford

Common orache

Common orache (Atriplex patula) is commonly found on both cultivated and waste ground, especially near coasts, throughout the British Isles.

The plant is closely related to the goosefoots, and may be difficult to identify for this reason, but goosefoot flowers are bisexual whereas those of the common orache are either male or female. Also, the female flowers are enclosed by two green leaf-like structures called bracteoles, which are up to half an inch long. After flowering, the bracteoles hide the fruit.

Male flowers are more open, but the sepals and green petals are almost alike in appearance.

The common orache grows up to 40 inches (100 centimetres) high, flowering in August and September. The stems are branched and are often coloured red. The leaves are toothed.

© John Welford

Common milkwort

Common milkwort (Polygala vulgaris) grows on heaths, grasslands and dunes. It has the unusual feature of having four possible flower colours, namely white, blue, mauve or pink. This has given rise to its alternative name (in Ireland) of “four sisters”. Its more common name arises from the fact that medieval herbalists used infusions of it to increase the flow of milk in nursing mothers.

Common milkwort is a small plant, growing up to 4 inches (10 centimetres) in height. The stems have many branches and are woody at the base. The leaves grow on alternate sides up each stem.

The flowers of the common milkwort are unusual and attractive. Each one has five sepals, three of which are green and small but the other two are coloured and much larger. The eight stamens link together to form a tube which only just protrudes beyond the coloured sepals. One petal is much larger than the others, which are very small and are joined to the stamen tube. The larger petal is on the underside of the flower and has a fringe. The flowers appear from May to September.

The fruit of the common milkwort is flat and transparent.

© John Welford

Common mallow

Common mallow (Malva sylvestris) is often seen on waste ground and roadsides throughout the British Isles, although it is rarer in the far north of Scotland. It is related to plants such as hollyhock and hibiscus.

It grows to a height of up to 36 inches (90 centimetres). The leaves at the base are rounded but those growing off the stems are more like ivy leaves in shape. The flowers, which appear from June to September, are pink to purple and one to two inches across. They have five narrow petals that are marked with dark veins. The fruits are round and comprise a ring of nutlets; these have given rise to folk-names for mallow such as ‘billy buttons’ and ‘cheese flower’.

In ancient times mallow shoots were eaten as a vegetable, and the plant has also found medicinal uses. In medieval times it was believed that it acted as an anti-aphrodisiac for people who needed to be calmed down! More recently, its leaves have been used to treat wasp stings and the sap has been made into poultices and ointments.

© John Welford