406 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxv. 



The left shell is somewhat larger than the right and not armed 

 with tubercles at its anterior and posterior margins. The color varies 

 from brownish yellow to a clear yellow. 



Natatory setse of the second antennae reach slightly beyond the tips 

 of the terminal claws. Spines of the first maxillary process toothed. 



Terminal claw of the second foot slender, slightly longer than the 

 terminal segment. Furca (fig. 3) approximately straight, the termi- 

 nal claw about one-half its length; subterminal claw about two-thirds 

 the length of the terminal one ; dorsal seta about width of furca from 

 subterminal claw, and approximately as long as the claw; terminal 

 seta slender, nearly one-half length of terminal claw. 



A large number of these forms were found in recent indurated mud 

 deposits near Carlisle, Pennsylvania. The specimens were picked 

 from the dried mud, soaked in a solution of potassium hydroxide for 

 a number of hours, then placed in dilute glycerin. In this manner 

 the apparent^ hopelessly dried specimens were put into such condi- 

 tion as to permit of dissection. 



Kaufmann," speaks of this form as not being sexual except possibly 

 in favorable localities, while Midler, 6 speaks of this form as being 

 occasionally sexual. Xo doubt most, if not all. Entomostraca may 

 prove to be both sexual and parthenogenetie, depending upon the 

 surrounding conditions, so much so that this character may prove of 

 slight value either as a generic or as a specific character. 



Distribution, Europe, Asia, and America. 



4. SPIROCYPRIS Sharpe, 1903. 



io. SPIROCYPRIS TUBERCULATA, new species. 



Plate L, figs. 1, 1'; Plate LIV, fig. 4; Plate LV, tiz*. 1-6. 



Dimensions. — Length, 0.03 mm. ; height, 0.53 mm. ; breadth. 0.7 mm. 



A beautiful purplish brown tuberculate form, always showing a 

 transverse dorsal band of a lighter color in region of the eye-spot, 

 and occasionally another similar band similarly situated posteriorly. 

 Preserved specimens show these bands rather indistinctly, the general 

 purplish color showing, however. 



The shell ( Plate L, tigs. 1. -J) is thickly covered with a large number 

 of unusually large and prominent papillary elevations. This feature 

 is so strikingly apparent as at once to distinguish the species, even 

 neglecting the color markings, which are also unusual. Shell also 

 covered with short hairs, mostly situated upon the tubercles. 



Seen from the side ( Plate LIV, tig. I ). the shell is nearly the same 

 width throughout, both extremities evenly rounded, and fully four- 

 sevenths a- high as long. 



" Revue Suisse de Zool., VIII, 1900, p. 2G8. 

 &Zoologica, XII, 1900, p. 79. 



