322 



of which the 1 st is very small; the 2 nd is enormously expanded at 

 the sides , and the last , which doubtless represents the dorsal elements 

 of more than one true segment , also much enlarged , expanded late- 

 rally and posteriorly, so as to entirely cover the anal region. — The 

 anus is protected laterally and above and more or less below by 

 horny plates, but the anal valves and sternite are not completely em- 

 braced by a ring-like last segment of the body. A typical body seg- 

 ment consists of a vaulted semi-circular tergite, constituting the 

 dorsal plate, and a flattened ventral surface, upon each side of which 

 there is a single pleural scute, the middle of the lower surface being 

 occupied by a soft membrane, to which the six-jointed, contiguous 

 legs are articulated; there are for the most part two legs on each 

 side to each pleura and between the pleurae and the basal segment 

 of the legs there are two freely movable tracheal plates or pedal la- 

 minae, one corresponding to each leg. 



The terga are not furnished with repugnatorial pores, nor are 

 there setae corresponding to the position of the pores. 



The legs of the 7 th segment are unmodified in the <? ; but the last 

 or last two pairs in this sex are transformed into an organ of copu- 

 lation. 



Family GLOMERIDAE (s. s.). 



Glomeridia, Brandt, Bull. Mose. 1833, p. 194. 



Antennae relatively close together on the anterior surface of the 

 head ; eyes consisting of a lateral vertical series of ocelli ; between the 

 eyes and the joint of the antennae their is a conspicuous horse-shoe 

 shaped (sensory) organ. 



Gnathochilarium with the mentum and lingua distinct, the latter 

 narrowed distally; the cardo small, the stipes twice as long as the 

 cardo and furnished with two malae. 



Twelve (rarely eleven) distinct tergal plates , and on each side ten pleu- 

 rae supporting the ambulatory limbs ; the pleura of the 2 nd segment pre- 

 sent, that of the 1 st obsolete, the anterior four terga with a pair of legs 

 each, the 5 th to the 10 th with two pairs, the 11 th with one pair; 

 the 12 th (the anal), representing apparently two segments, without 

 legs in the 9, but provided with two pairs (copulatory) in the c?. 



(? The last segment apodous its pleurae transformed into the anal 

 valves.) 



