Insects are perhaps the most familiar invertebrates. They belong to a group of animals known as arthropods that also includes spiders an crabs. Adult insects have six legs and a body made up of a head, thorax and abdomen. Many also have one or two pairs of wings; they are the only invertebrates that can fly. A hard exoskeleton made of chitin supports their soft bodies.
In the same way as crustaceans rule the oceans, the insects rule the land. They exist in almost every terrestrial environment, and in an enormous array of colours, shapes and sizes. Many of them have fascinating life histories.
Vile or vital?
Insects often have a bad reputation for being creepy, scary or just a complete nuisance. Whilst bees may sting us if we sit on them or get too close to their nests, we rely on them to pollinate our crops. Without them performing this vital role it would be very difficult to produce food – the bees are the farmers’ best friend!
Other insects are responsible for keeping the soil fertile (e.g. dung beetles) or eating smaller insects that damage the plants we grow (e.g. ladybirds feed on greenfly). Scale insects produce a red dye called carmine. Since the time of the Aztecs carmine has been added to foods, textiles and cosmetics.
RAMM’s insects – keeping them safe
RAMM’s collections include specimens from all the major insect groups:
Lepidoptera – Butterflies and moths
Coleoptera – Beetles
Diptera – True flies
Hymenoptera – Bees, ants and wasps
Orthoptera – Crickets and grasshoppers
Hemiptera – True bugs
Odonata – Dragonflies and damselflies
Mantodea – Praying mantids
Phasmida – Stick and leaf insects
RAMM’s insects are in drawers with a tightly fitting wood and glass lid to keep out live insects. Pests such as the carpet beetle which will feed on the dead insects and destroy the collection. Most insects have a pin through their body to fix them to a cork or plaztazote lining in the drawer. It also means all parts of the insect are visible.
The pin also holds labels that give information about the specimen such as collection location and date. The information that accompanies a specimen is very important, particularly its collection location and date. Other information such as whose collection it came from can often be figured out from the handwriting or type of label if this information is not given.
Butterflies and Moths
RAMM has over 120,000 butterfly and moth specimens. It is one of the finest, most extensive and scientifically valuable collections of any provincial museum in the country. It includes eggs, larvae, pupae and adults.
Butterflies and moths are among the most majestic of insects. Their vivid colours and striking patterns are mesmerising both in nature and in museum collections. Transient, fluttering and fragile, or adept flying machines, these wonderful creatures are one of the highlights of RAMM’s natural history collections.
The size and quality of our collections is largely thanks to the dedication of Major Bertie Gay and Anthony Adams who painstakingly sorted the specimens into consolidated collections that were arranged in taxonomic order. Major Gay also purchased, from his own pocket, a considerable number of rare and tropical specimens for the collections as well as numerous cabinets for their storage.
Empty pupal cases and cocoons are relatively simple to preserve, but larvae are much more difficult due to their soft bodies. When larvae dry naturally they shrivel and lose the appearance they had in life. The easiest way is to store them in a fluid such as alcohol, but this can make them difficult to study and cause them to lose their colour.
As a result collectors had to come up with an ingenious method of preservation. The insides of the larva would be squeezed out of a small puncture in its rear end. Then a very fine glass tube is inserted through the puncture allowing the larva to be inflated while drying the skin over a heat source. Next it is mounted on a piece of wire for display in the cabinet. These larvae are extremely fragile – they are a little like a tissue paper balloon.
Beetles are the most diverse insect order. Over 300,000 species are described and many thousands still to be described and discovered.
From the tiny to the tremendously large, beetles exist in all shapes and colours. One of the largest beetles in the world is the goliath beetle which can measure up to 11cm in length.
Some species are known as jewel beetles because of their beautiful metallic wing cases (elytra) that protect the flight wings beneath them. This metallic colouration is not made by a pigment but by iridescence. Some butterflies are also iridescent. It happens because of the way the structure of the beetle’s exoskeleton reflects light. Due to this, the beetle’s colouring will not fade even after many years in our collections.
The majority of RAMM’s beetle collections exist thanks to the efforts of three collectors:
Philip Le Hardy de la Garde
De la Garde collected many beetles and other natural history specimens during his Naval career, particularly from the Plymouth area when he was based at Devonport. During his retirement he made collections in Teignmouth and Braunton. He left his collections to the RAMM in his will in 1913.
John Joseph Reading
John Reading is one of the most famous Plymouth entomologists. He was a curator of entomology at the Plymouth Institution from 1861 to 1863. He left Plymouth in the early 1870s and his collections came into the possession of Brooking Rowe who later presented them to RAMM in January 1904. This donation included a 40-drawer entomological cabinet. Reading had extensive and accurate records of his captures and sightings. He was involved with several important (re)discoveries.
S.G. Rendel, then living in France, donated his collection of British beetles to the Museum in May 1928. Many of the specimens came from the Tiverton area. Unfortunately we know little of his life history.