Fresh-water Entomostraca of South America. 47 



the length, dorsal margin almost straight in its posterior 

 part, and terminating with a distinct, though obtuse corner, 

 posterior edge rather obliquely descending, lower edges, as 

 in the preceding species, fringed with strong setse, surface 

 of valves only marked near the edge with concentric rows 

 of faint punctures. Head somewhat procumbent, with the 

 dorsal margin evenly arched, rostral projection rather pro- 

 duced, though not nearly to such a degree as in the pre- 

 ceding species, and but slightly curved. Eye about as in 

 L. curvirostris ; ocellus, on the other hand, of quite an extra- 

 ordinary size, being more than 3 times as large as the eye 

 and of an irregular quadrangular form. Antennæ with none 

 of the setæ remarkably elongated. Lip-plate with a small 

 dentiform projection below near the tip. Caudal part con- 

 siderably produced, but much narrower than in the pre- 

 ceding species, dorsal edge below the anal orifice almost 

 straight, lower corner forming a somewhat projecting, broadly- 

 rounded lobe, spines of the marginal rows numbering about 

 20 on each side, increasing in size distally, supra-anal projec- 

 tion rather slight, caudal claws finely denticulated through- 

 out the greater part of their length. Colour reddish orange. 

 Length of adult female 0.80 mm. 



Ke marks. — Though evidently congeneric with the 

 preceding species, this form is at once distinguished by the 

 less prolonged rostral projection, the extraordinary size of 

 the ocellus, and the rather different form of the caudal part. 

 Moreover, the setæ of the antennæ are far less elongated. 



Occurrence. — Only a few female specimens of 

 this form were found in one of my aquaria that was pre- 

 pared with mud from Sâo Paulo. In habits it exactly agreed 

 with the preceding species, and both the size and the colour 

 were about the same. 



