774 CHARLES PAuL ALEXANDER 
Larva.— Head oval to subpyriform, broadest behind, narrowed. in front, not heavily 
patterned above; setae of head branched or plumose. Submentum large, usually but a little 
narrowed posteriorly, the anterior lateral angles slightly produced; mentum broader than 
long, outer margin with numerous teeth (18-22). Prementum with. palpi rather small, 
lying parallel, densely hairy on outer, or ventral, face. Mandible with three powerful outer 
teeth and about six smaller inner teeth. Maxilla with the cardines elongate-triangular, 
with three setiferous punctures; maxillary palpi antenniform, cylindrical. Labrum_ broad, 
transverse, with dense tufts of hair beneath. Integument almost smooth, without prominent 
warty elevations. Pseudopods low, with small claws. 
Pupa.— Head small, with a reduced cephalic crest. Sheaths of maxillary palpi elongate, 
the tips projecting around knee joints of fore legs. Leg sheaths with all the tarsi parallel, 
not overlapping one another. Wing sheaths with media branched. Pronotal breathing 
horns very unequal, one (usually the right) exceedingly elongate, longer than remainder 
of body, the other tiny, degenerate. Abdomen set with transverse and longitudinal rows 
of small setiferous tubercles on the segments. 
Ptychoptera is a small genus including sixteen described species, almost 
all occurring in the Holarctic region, with a few species in India and 
Formosa. Two species are found in tropical Africa, and another, an 
undescribed form, in southern South America; hence the genus is probably 
found thruout the world in countries in the temperate zones, with the 
probable exception of Australia. 
The literature on the immature stages of this genus is summarized 
under the family account. 
Topsent (1914-16) has furnished the best account of any species of 
the genus Ptychoptera. His observations refer to Ptychoptera albimana. 
The following notes are extracted from Topsent’s paper: 
The eggs range in number from 520 to 587, averaging 554. They are pale yellow, slightly 
arcuated, the surface curiously ornamented, the dimensions being 0.825 by 0.264 millimeters. 
The duration of the egg stage is seven days. The newly hatched larva measures 3.85 milli- 
meters, the respiratory -tube 0.99 millimeters.. The adult larva measures 77 millimeters, 
of which the respiratory tube is 20 millimeters. The growth of the larva is rapid: When 
fifteen days old it measures, when extended, 25 millimeters. When sixty-seven days old, 
it measures 45 millimeters. The pupal stage is from ten to twelve days, averaging eleven 
days. There are normally two generations a year. 7 
De Meijere (1916:188-191) gives a critical account of the structure 
of the larva of a European Ptychoptera. It agrees well with the description 
of P. rufocincta given below, the most conspicuous differences shown by. 
De Meijere’s species being as follows: labium with the submentum having 
the sides straighter; mentum with the anterior margin evenly, but gently, 
convex, with only eighteen evident teeth. The details of the maxilla, 
