80 



these caterpillars hold tight bv the third pair of legs, and erect the 

 anterior part of the body, spreading out the first 

 and second pair, and endeavouring to look formid- 

 able, at the same time curling the posterior part 

 of the body, as represented in the accompanying 

 sketch, and protruding a yellow appendage from 

 the telum : I also observed that a thick yellow juice 

 was exuded from the last two or three segments. The legs are of a 

 ])ale yellow colour. I have set a person to watch one or two of the 

 masses in his garden, and see what becomes of them. They grow to 

 be as large as a full-grown larva of Ceriu^a Yinula. 



Your's &c. 

 To the Editor of A. H. Davis. 



' The Entomologist.' 



[It appears to me that the caterpillar mentioned and drawn by Mr. 

 Davis, must be tenthredinidous ; the manner of erecting the anterior 

 legs and of curving the tail seems to favour this oj^inion, while the 

 size, that of a full-grown larva of Cerura Vinula, I must acknowledge 

 to be rather startling, for the largest New Holland Tenthredinites with 

 which I am acquainted are those of the genus Perga, a new and beau- 

 tiful species of which Mr. Davis has sent me, together with a pair of 

 minute insects belonging to the same natural order, but apparently of 

 a genus hitherto uncharacterized. I append descriptions of both 

 these novelties. 



Genus. — Perga, Leach. 



Perga hella. Testacea : caput testaceum, oculis nigris ; ocelli ni- 

 gri in macula concolori siti ; antennarum articuli 1 et 2 aterrimi, 

 apicibus tenuiter albis, 3 fuscus, caeteri lutei ; antenna tubere 

 albo sita) ; oculorum margo anticus albus, genae quoque alboe ; 

 epicranium asperura, maculis 2 albis signatum ; clypeus testa- 

 ceus, lateribus albis: prothoracis scutellum margine posticaalba : 

 mesothoracis scutum asperum, punctum, linea mediana margi- 

 nibusque lateralibus elevatis albis, lineis quoque nonnullis nigiis; 

 mesothoracis scutellum dentibus 2 posticis sublongis obtusis in- 

 structum ; mesopleura puncta, margine imo falciformi late albo : 

 metapleura nigro varia, macula elevata mediana subtrigona alba: 

 mesosternum aterrimum glaberrimum : pedes flavidi coxis albis : 

 abdomen testaceum, maculis 7 lateralibus elongatis albis, sub- 



