THE CANADIA.N ENTOMOLOGIST. 221 



segments, or shorter (Embia), the apical joint thinner, cyHndrical. If 

 asymmetry is present, the left appendage has the basal joint shorter, 

 larger, sometimes almost quadrangular. Between these appendages are 

 situated the external genital organs of the male. They consist of a middle 

 more or less inflated conical or cylindrical membranous part, with a cir- 

 cular opening on tip, representing probably the intromittent organ ; on 

 each side is a horny spine, long, narrow, more or less pointed and twisted, 

 asymmetrically in a different manner. The spine of the right side seems 

 to present its regular more or less straight form ; the left spine is twisted 

 similar to a corkscrew in its apical half, and so nearly approximates to the 

 intromittent organ that it is clearly to be seen only in alcoholic specimens. 

 In all males, where these characters could be well seen (at least in Oli- 

 gotoma), more or less asymmetry was evident, and McLachlan, 1. c. p. 

 378, is of the same opinion. The last dorsal segment of the males is 

 also asymmetrical, with a deep impressed fold nearer to the right side, and 

 the apical margin is cut obliquely ; the last ventral segment is also asym- 

 metrically protruded. My description of these parts is made only from 

 winged males, but Wood-Mason, 1. c. p. 630, says that the larvae of O. 

 Saundersii collected by him in numbers at Jubbulpore, and without the 

 slightest traces of wings, possessed all the same characteristic asymmetry 

 quite apparent, which he considers exclusively confined to the male sex. 

 He adds that " the asymmetry of the tergum of the terminal abdominal 

 somite and of the cerci in Necrosia maculicollis (Phasma) appears at the 

 corresponding early stage, and is in nymphs quite as strongly marked as 

 in perfect insects." I am sorry that this insect is not at my disposal, 

 nor can I compare Westwood's Oriental Cabinet. In his catalogue of 

 Orthpptera, Westwood does not mention any asymmetry. I think that 

 the shape of these organs is never expressed in the larvae in a similar 

 manner as in the imago and in the nympha. Till the contrary is proved, 

 there must remain some doubt if these so-called larvae do not perhaps 

 belong to a wingless form of the imago. 



I have not seen winged females, but in the wingless female, which is 

 said to belong to O. Michacli, and in Olyntha Afulieri, no asymmetry is 

 apparent. Not one of the icw wingless forms before me considered to be 

 larvae, is asymmetrical, but those parts are mostly too much shrivelled up 

 in dry specimens to enable one to be certain. 



The female opening is at the base of the notched 7 th segment, similar 

 to those of the Termitina. The same arrangement of the genitals of the 



