FRESH-WATER BIOLOGY 



Inner margin of basal segment of male clasping antenna without a 

 tubercle but with a spiny area near proximal end. 



Branchinecta lindahli Packard i88^. 



The body is robust; the caudal appendages are comparatively long; 

 the eggs are small, and the ovisac usually contains about fifty of them. 



A plains species recorded from Kansas, Nebraska, Colorado, and 

 Wyoming. It is known to occur as high as 7500 ft. above sea level. 



Fig. 1020. Branchinecta lindahli. Headof male, front view. X 3. (After Shantz.) 



15 (8) Post-genital region 8-segmented, apical article of male clasping antenna 

 compressed Artemia. 



Only one species. . . . Artemia salina (Linnaeus) 1851. 



Connecticut, Utah, California, Lower California. This species is 

 remarkable for its ability to live in extremely saline water. It is 

 frequently found in salt evaporating basins. The form is variable, 

 and several varieties have been described. 



Fig. 1021. Artemia salina. Head of male, dorsal view. X 4. (After Daday.) 



16 (7) Head of male often bearing a frontal appendage or a laminar appendage 



on the basal segment of the clasping antenna. 



Family Chirocephalidae . . 17 



17 (30) Frontal appendage of male variable, rather short; terminal segment 



of copula tory organ smooth Euhranchipus . , 18 



18 (25) Body segments of male and female all superficially unarmed. . . 19 



19 (20) Frontal appendage of male short, about as long as basal joint of sec- 



ond antenna; lanceolate, margin denticulate. 



Euhranchipus vernalis Verrill 1869. 



Massachusetts, New Jersey, Indiana, Michigan. This species 

 appears in small quiet pools soon after the snow disappears in spring, 

 or even in mid-winter, but has not been observed during the summer 

 months. 



Fig. 1022. Euhranchipus vernalis. Head of male, side view. X 4. 

 (After Packard.) 



Frontal appendages of male when extended longer than basal joint 

 of second antenna 21 



Frontal appendages of male attenuate, middle fourth serrate. 



Euhranchipus holmani (Ryder) 1879. 



This species was first discovered in 

 New Jersey and has since been ob- 

 served on Long Island, New York. 

 Packard ('83) confused this species 

 with Branchinella gissleri Daday. 



Fig. 1023. Euhranchipus holmani. Head 

 of male; yi, side view; 5, front view. 

 X 4. (After Daday.) 



22 (21) Frontal appendages of male broad, lanceolate, lobate on margins. 23 



