438 Transactions of the Society. 



Of the large Continental Ethiopian species, I have mounts of 

 E.fuscum from Kuako, E. occidentalc from Entebbe, E. a/rum from 

 Entebbe and from Spanish Guinea, and E. occidental from the 

 Kamerun (PI. VII. figs. 8 to 11). I can find no specific distinction 

 in their genital armature, and consequently feel obliged to regard 

 them as mere colour variants of the original species, E. afrum of 

 Palisot de Beauvois. 



These three principal Ethiopian species may accordingly be 

 tabulated as follows : — 



1. Metaparameres arcuate, and apically truncate . E. bolivari Rodz. 

 1, 1. Metaparameres straight and angustate. 



2. Virga moderately long . . . . E. afrum Beauv. 



2, 2. Virga very long and convoluted • . E. walilbergi Dohrn. 



The genitalia of the Indo-Malayan E. sumatranum agree very 

 closely with those of E. afrum, and those of the small Cingalese 

 E. parvulum are almost the same (PI. VIII. fig. 3). 



In the latter the virga is short and nearly straight ; the hinge is 

 only visible as a thickening in the chitin. 



Sub-family 6. Allostethin^e. 



This group has been discussed in great detail by Zacher. The 

 metaparameres are narrow, long, and lanceolate ; the virga is rather 

 broad basally, attenuate gradually. It is not very clearly figured 

 by Zacher. We meet here for the first time with a fine spiral net- 

 work, called by Zacher " Spiralversteifung," which is so familiar 

 a feature in the later groups ; it remains to be seen whether its 

 function is, as Zacher' s name suggests, a protective apparatus to 

 give rigidity to a delicate structure, or whether it is a muscular 

 contrivance for the contraction of the virga to effect or assist 

 ejaculation. It is only seen where the virga is inflated to form a 

 vesicle, or the beginning of a vesicle, as in this sub-family ; in 

 appearance it resembles the armature of the trachea?. 



Zacher states in a general way that the virga is relatively 

 short, only about one-third of the length of the penis ; this is true 

 in Allostetlms and Gonolabidura, but in Allostcthella doriiv the 

 virga is much longer (PI. VIII. figs. 8 and 9). As the preputial 

 sac is an elastic organ, it is better to compare the length of the 

 virga with the rigid metaparameres. From Zacher' s figures the 

 virga appears to be a little more than half as long as the metapara- 

 meres in A. indicum and less than half as long in Gonolabidura 

 volzi, and a trifle longer in Allostcthella malayana Zacher. In Gono- 

 labidura astruci Burr it is about half as long as, and in Allostcthella 



