266 Mr. Newport on the Class Myrlapoda, Order Chilopoda, 



unrestricted access to the cabinets in the British Museum, through the libe- 

 rality of the head of the department, J. E. Gray, Esq., to that of the Museum 

 of the gentlemen of the United Service, of the Zoological Society, and also to 

 the Linnean and Banksian cabinets. These means of research have enabled 

 me not only to identify many of the species originally described by Linneeus 

 and Dr. Leach, and to add considerably to the number of new species, but 

 also to deduce conclusions respecting the whole class. Part of these results, 

 which refer to the Chilopoda, I now propose to do myself the honour of sub- 

 mitting to the Linnean Society. 



The Myriapoda may be characterized as an osculant class of invertebrated 

 apterous animals, that typify, as a permanent condition, the transitory form of 

 the larva state of insects. One division of these animals has relation to the 

 rapacious and active Arachnida, and the other to the strong-bodied, lignlvo- 

 rous Crustacea. In each division the head of the Myriapod is distinct from 

 the body, and is furnished with a pair of antennae ; and the body is elongated, 

 and divided into many uniform, moveable segments, of which, in the adult 

 state, there are usually more than fifteen, and never less than twelve. Each 

 of these moveable segments gives origin to one, and sometimes to two pairs 

 of legs. The Myriapoda respire atmospheric air by means of spiracles and 

 ramified tracheae. They leave the ovum in an incompletely developed em- 

 bryonic form, and afterwards undergo many changes of tegument or pseudo- 

 metamorphoses, at each of which the body acquires an addition of segments 

 and legs, until the animal has obtained its adult number; after which it 

 merely continues to increase in size at each change. 



Linnaeus and the older naturalists arranged the Myriapoda with apterous 

 insects, and even now* they are regarded by some as constituting only a 

 division of the great class Insecta. But although they approach very closely 

 in their general appearance, internal anatomy and modes of life to the larva 

 state of insects, they nevertheless differ quite as much as the Crustacea and 

 Arachnida, which almost every modern naturalist has separated from the true 

 Hexapods. The manner in which the Myriapoda acquire their perfect state, 

 by an extension of, and an addition to, rather than by a shortening of the 

 body, is so dissimilar to the changes in insects that it fully entitles them to be 



* Brandt. 



