1915] 
Muttkowski: New Insect Life Histories 
19 
pointed out that in the first determinations made according to 
Johannsen’s tables the larvae appeared to be those of Thalassomyia 
while all the pupae belonged to Diamesa. If Professor Johann- 
sen’s assignment of his larvae to Diamesa waltlii and Thalassomyia 
ohscura were in accordance with true conditions then the discovery 
of Diamesa mendotae would be of considerable phylogenetical 
significance because of the disparity of proper larval and pupal 
characters. It seems, however, much safer and much more 
simple to assume an inadvertent interchange of larval specimens 
on the part of Dr. Johannsen. 
Fig. 4 Diamesa mendotae n. sp. Pupa. Dorsal and ventral view. 
THE PUPA 
Length, 6-8.2 mm. 
Color, fuscous or brown, although yellowish green when fresh. Nearly 
mature pupae show the thoracic region and wing sheaths nearly black. 
Wing sheaths attaining the base of the third segments ventrally. Ap- 
parently no respiratory filaments present in the thorax; yet exuviae show 
a hollow filament each side of the dorsum a little distance behind the head. 
Abdominal segments gradually tapering. Dorsally the posterior mar- 
gin of each segment except the first and last with a varying number of 
black teeth, twelve to fifteen on the second segment, gradually decreasing 
to about eight on the penultimate segment; middle spine shorter, usually 
each alternate spine larger. Ventrally segments three to seven of the 
abdomen with about eight teeth on the posterior margin, these teeth very 
small on three, prominent and black on four to seven. Segment eight 
ventrally with two pyramidal prominences, each with an angular tip, 
although not black. 
