82 Journal New York Entomological Society. [Voi. v. 
The thorax is very convex, there are two high prominent tubercles 
on the scutellum, which are higher and longer than in Andrew, also 
two smaller ones on the meta-scutellum (none on the port-scutellum). 
The propodeum is more like an abdominal segment than a thoracic one ; 
it is broad and square-cornered, twice as broad as long, not yet sepa¬ 
rated from the abdomen. The latter is now one-half larger than the 
head and thorax. The segments posteriorly are very convex, and the 
edges very distinctly, thickly and finely dentate; the end or terminal 
segment of the abdomen is long and slender. 
The presence of the four deciduous semi-pupal tubercles on the head, 
which in this stage are so large and distinct, and which are arranged in 
a transverse line just in front of the ocelli, is interesting and deserves 
further investigation, as their use is unknown. The fact that all these 
tubercles disappear afterwards is of additional interest, also the circum¬ 
stance that they do not exist at all in the corresponding stages of Apis 
and of Bombus is perhaps a characteristic of that sub-family of Apidae 
(Andr ended) of which Halictus is a member. 
The pair of tubercles on the meso-scutellum and meta-scutellum are 
also of corresponding interest. They are scarcely homologous in po¬ 
sition with those of Oxybelus, except those on the meta-scutellum. The 
serrate, very convex abdominal segments are noteworthy, as being a 
“ low” feature. Also noticeable are the great differences between the 
two high posterior tubercles on the sides of which are situated the two 
posterior ocelli, so different from the anterior sunken ocellus. 
Andrena vicina Smith. 
Larva. _In Andrena vicina the larva is not only much larger, stouter 
and thicker than that of Halictus (AT. paratlelus and ligatus), and not so 
long in proportion, but the thickened tuberculous portion of the segments 
is broader, and not so sharply ridged. The two tubercles on the head 
are more prominent. The clypeus is wider and squarer, and the entire 
clypeal region broader ; the mandibles are stouter and blunter, as are the 
maxillae; the best characters are the stouter, more truncate mandibles, 
and the more raised tubercles on the vertex. 
Head with the vertex rather deeply impressed by the median line; 
on each side is a high, prominent, acute tubercle. The lateral region on 
each side of the depressed median portion bulging, convex. This median 
region is divided into two slightly convex pieces. The clypeus is divided 
into an anterior and a posterior portion. The labrum is nearly square, 
quite distinct from the clypeus; the edge is square, the sides narrowing 
very slightly towards the front edge. On each side of the front edge of 
