179 



The mandibles and maxillae, each with palpi, are terrible organs of attrition, 

 ■with their close set teeth. And even the great swimming foot only represents 

 the last pair of jaw-feet, for it is closely covered by the lower lip. There is no 

 instance in living adnlt Crustacea, of all the appendages being those of the head. 

 In Limulus, their nearest ally, the limbs represent both head and thoracic- 

 appendages. 



(Mr. Salter, as he described this new Pteryootus, sketched upon the black 

 board the portions discovered, and then supplied the outlines of the missing 

 parts in a very interesting and instructive manner.) 



The President then exhibited a case containing a splendid specimen of 

 the moth of the Bombi/x Yanm-Maia,, near four inches broad, whose deep orange 

 colour, with peacock eyes in the back wings, relieved by touches of lUac in the 

 front ones, produced a very striking effect. Its antennce were very bold and 

 beautifully cut. By its side was the empty cocoon it had left. The case also 

 contained several interesting moths and cocoons of the American species of 

 Bombyx, the Lophocampa Caryte. The hairs of this caterpillar sting like cowage, 

 and as they are used up in the fonnation of the cocoon, they require to be 

 handled with care. 



Dr. M'CnLLOtrOH then read a paper entitled 



X -I 



