with descriptions of new Genera and Species. 201 



E. pyriformis. Outline of body (viewed dorsally) nearly oval 

 with a slight constriction in the middle : lorica divided longitu- 

 dinally along the ventral surface, the gape widening anteriorly : 

 toes parallel-edged : eye minute. Lorica ^nd inch. 



E. hipposideros. Body nearly oval in outline ; the ventral side 

 flat ; the dorsal greatly arched, and ridged down the middle : 

 lorica formed of two distinct plates ; the dorsal plate enveloping 

 the back and reaching half down the sides ; the ventral separated 

 from it by a wide space, and hollowed in the middle so as to 

 present the figure of a narrow horse-shoe, whose points are for- 

 wards : foot armed with one pair of bristles. Lorica yy^th inch. 



Salpina spinigera. 



S. mucronata. 



S. brevispina. 



Gen. Diplax. Resembles Salpina, but the eye is wanting; 

 and the lorica (which, as in that genus, is cleft down the back) 

 is destitute of spines both in front and rear : foot and toes long 

 and slender. It forms a connecting link between Salpina and 

 Dinocharis. The name {BlirXa^, double) alludes to the gaping 

 lorica, which forms two parallel plates. 



D. compressa. Form of lorica (viewed laterally) nearly a 

 parallelogram, greatly compressed. Lorica y-f^th inch. Lea- 

 mington. 



D. trigona. Lorica three-sided, a section forming a nearly 

 equilateral triangle ; surface delicately punctured or stippled : 

 toes long and slender. Lorica y^th inch. Leamington. 



Dinocharis tetractis. 



D. pocillum. 



Colurus bicuspidatus. 



C. defleocus. 



C. caudatus. 



Metopidia lepadella. 



M. solidus. Much resembles M. lepadella, but is considerably 

 larger : lorica nearly circular, brilliantly transparent : a slight 

 puncturing runs round near the edge, like the legend on a coin. 

 Lorica yjoth inch. 



M. acuminata. 



M. triptera. 



M. oxysternon. Resembles M. triptera, but the dorsal keel is 

 much higher and thinner ; the anterior two-thirds of the ventral 

 surface form a prominent ridge terminating abruptly like the 

 breast-bone of a bird ; and the posterior portion is hollowed out 

 remarkably. Viewed laterally the outline of the back is very 

 gibbous behind. Lorica yjjth inch. 



Stephanops lamel/aris. 



S. muticus. 



