126 PACKAED, HUMBLE BEES, ETC. 



tip a little obtuse and incurved. The legs are large and 

 long, with stout joints and strong claws : the femora are 

 dilated, the tip of the tibiae much enlarged : and the 

 tarsal joints are broadly triangular. 



Notes on an unknown larva allied, to that of Volucella. . 



Westwood (Intr. n. p. 558) states that the " larvae of Vol- 

 ucella reside in the nests of Bombi and Yespas, upon the 

 larvge of which they subsist ; they have the body long, nar- 

 rowed in front, transversely wrinkled, with fine lateral 

 points, and the tail armed with six radiating points ; the 

 mouth is armed with two bifid mandibles, and with three 

 pairs of tentacula." The pupse of this genus have not 

 been described, DeGeer figuring only the larva and imago 

 of V. bombylans (Mem. torn. vi. tab. 8. fig. 4 — 9 ; and see 

 Reaumur, Mem. torn. iv. pi. 33.) 



Several nests of Bombus fervidus and B. vagans were 

 found by Mr. Putnam to be infested by larvae which it 

 will be seen agree in many respects with the above 

 description of those of Yolucella. 



They were 13-jointed. The terminal triangular portion 

 appears to consist of a single ring, though in reality made 

 up of three segments soldered together. In form the 

 laiwaa are oval lanceolate, narrowing in front, and the 

 dorsal surface is convex continuously from the head to 

 the anal tip, and beneath flattened : with two dorsal and 

 two lateral rows of stout bristles spinulated at the base. 

 The head is broad oblong, flattened from above ; it is 

 nearly as long as the pro-thoracic' ring, and two-thirds as 

 broad ; very scpiare in front, the sides are parallel and very 

 slightly convex, arising from the front edge of the head, 

 and above the mouth are two minute seta? which do not 

 appear to be jointed, or to differ structurally from the 

 other spinules upon the surface of the body, except 

 that they are simple ; these are all the appendages to the 

 head that can be seen when the mouth is retracted: in 

 one specimen however where the mouth is partially 

 thrust out there is seen attached a v-shaped organ (max- 

 illae '!) such as are described as occurring in Yolucella : on 



