398 CHUSTACEA OF LAKE UEMI. 



characters of doubtful taxonomic value. Artemia salina^ A. 

 miUhause^iii, A. fertilis, A. gracilis, A. monica, and A. utaJiensis 

 have all been distinguished by characters which vary to a greater 

 or less extent with the salinity of the water in which they live. 

 I am inclined to agree with Packard that only two well-defined 

 species o^ Artemia have been described, viz., the Old-World form 

 A. salina, with which A. mulhausenii (or Artemia sp. gr. 1"2015) 

 has been proved by Schmankewitsch to be identical, and the New- 

 World A. gracilis, including Verrill's other American species as 

 synonyms. At the same time it is possible that, when a complete 

 revision of the group is made and more minute details are taken 

 into account, other and better specific differences may be found 

 to exist. In the meantime, in order to attract notice to its 

 peculiar features, I venture to propose Artemia unjiiana as a new 

 Old- World species, with the following diagnosis : — 



A. UEMiANA, sp. n. 



B/Csembling A. salina, but with an incompletely-segmented 

 abdomen ; furcal lobes bearing a single seta apiece in the male 

 and none in the female ; claspers of male of larger size than in 

 the male A. salina ; labrum with two sensory setose papillae, 

 The margin of the fifth endites of the thoracic feet bordered 

 with short setse bearing barbs of peculiar nature. 



Hub. Lake TJrmi, in water of specific gravity 1"1138. 



EXPLANATION OF PLATE 25. 



Fig. L Artemia urmiana, sp. n. Ventral view of male. X 15. 



2. a. Ventral \iew of head of female. X io. b. Ventral view of ovisac of 



female. 



3. Lateral view, showing the position of the male when in the act oi 



clasping the female. Twice natural size. 



4. a. Pcstabdomen of c? Artemia urmiana. b. Postabdomenof 2 Artemia 



urmiana. c. Postabdomen of 2 Artemia salina (Coll. Norman). 



5. a. The ventral margin of the seventh thoracic natatory appendage. X40. 



The flabellum and bract are indicated by dotted lines, b. Barbed 

 setae from margin of the fifth endite. X 400. c. Sensory seta. 



