22 G. O. SARS. M.-N. Kl. 



The testes are located between the winds of the intestine, and are 

 apparently divided into several bag-like divisions. Their efferent ducts 

 enter the tail at its ^^cntral side, and run along tlie anterior edge until 

 the tip, where they arc continued into the above mentioned cylindrical 

 appendages. 



In both sexes tlie colour appears more or less vivid blood-red, which 

 colour chiefly affects the enclosed body, whereas the valves are more 

 pellucid, and of an orange hue. 



Observations. This Lynceid developed rather plentifully in some 

 of my aquaria, and in one of them has been domesticated until the pre- 

 sent time. 



As with other Lynceids, it is a true bottom-form, burrowing with 

 great dexterit}^ within the loose deposit at the bottom. It is therefore 

 most frequendy found on the floor of the aquarium, but at times 

 it may also be seen to ascend the walls generally on the side 

 turned to the light. It moves through the water rather slowly, by 

 rapid strokes of the antennae, whereby a rather even, though somewhat 

 trembling run is effected, the body being generally kept in a horizontal 

 attitude, with the back downwards. The males were onh^ observed at a 

 very restricted period of the season, but at that time rather abundantly. 



Distribution. Russia, Germany, British Isles, Sweden. 



Gen. : Alonopsis, G. O. Sars. 

 8. Alonopsis Colletti, G. O. Sars, n. sp. 

 (PI. 4, figs. 5-8)- 

 Specific Characters. Carapace of female much compressed, seen 

 lateral!}', oval quadrangular in form, greatest breadth anteriorly, posterior 

 extremity nearly transversely truncated, with the lower corner rounded 

 and unarmed, dorsal margin boldly curved in front, inferior edges sub- 

 flexuous in the middle. Head slightly erect, terminating in a compara- 

 tively short and obtusely acuminate rostrum; fornix rather prominent. 

 Surface of shell nearh" smooth, with a very faint trace of reticulation, 

 inferior edges of valves finely ciliated, and excised in front of the middle, 

 so as to leave, ventrally, an open oblong oval space leading to the inner 

 shell-cavit}'. E3"e of moderate size. Ocellus smaller than the eye, and 

 occurring nearly in the middle between the latter and the tip of the 

 rostrum. Antennulæ narrow snbfusiform, and not full}' extending to the 

 tip of the rostrum. Antennæ of moderate size. Tail slender, and con- 

 siderably narrowed distalh', tip incised behind the base of the terminal 



