Fresh-Water Entomostraca from China and Sumatra. 21 



tinguished by a very conspicuous spiniform process issuing 

 from each valve in about the middle of the posterior edge 

 and pointing straight behind. Natatory setæ of inferior an- 

 tennae extending somewhat beyond the terminal claws. 

 Caudal rami narrow and elongated, ^lightly curved in their 

 distal part, and very finely ciliated along the dorsal margin, 

 outer apical claw not attaining half the length of the ramus, 

 inner considerably shorter, apical seta very slender, dorsal 

 seta small and occurring near to the inner claw. 



Colour. — Shell semipellucid, with a fine violaceous 

 tinge, and variegated with irregular dark bluish patches, 

 each valve exhibiting along the free edge a narrow stripe 

 of same colour. 



Length of shell 103"^"^, height 057 ™in, width 052 '""i. 



Remarks. — I think I am right in identifying the above 

 described form with that briefly recorded by Baird under 

 the above name. As shown by the structure of the several 

 appendages, it undoubtedly ought to be referred to the genus 

 Cypris (sensu strictiore), exhibiting, as it does, the charac- 

 teristic slender and narrow form of the caudal rami and 

 of the digitiform lobes of the anterior maxillæ. It ma}^ be 

 easily recognized from the other species by the peculiar 

 colouring of the shell, well indicated by the specific name 

 proposed by Baird. 



Occurrence and Habit s. — This beautiful form devel- 

 oped rather abundantly in some of my aquaria prepared 

 with mud from Sumatra, and was watched during 2 suc- 

 cessive seasons. In habits it agrees with the other species 

 of the genus, being enabled to swim rather quickly through 

 the water by the aid of the antennæ, both pairs of which 

 are provided with well-developed natatory setæ. The pro- 



19 — Archiv for Math, og Naturv. B. XXV. 

 Trvkt 29. Juni 1903. 



K^ 



