654 



FRESH-WATER BIOLOGY 



24 (25) Much depressed; papillae numerous; no accessory eyes; size large. 



Placobdella rugosa (Verrill) 1874. 



25 (24) Moderately depressed; papillae less numerous; neural annulus with 



much dark pigment; several pairs of simple accessory eyes 

 succeeding compound eyes; size medium. 



Placobdella hollensis (Whitman) 1892. 



26 (23) Numerous minute papillae around margin of caudal sucker. Mod- 



erately depressed; dorsal papillae usually in a median and 

 two paired series, small, acute and pale yellow or brown; a 

 very conspicuous and constant pale band across somite VI; 

 size small Placobdella phalera (Graf) 1899. 



27 (14) Eyes four pairs, all simple; gastric ceca nine or ten pairs; salivary 



glands diffuse; body very soft and almost oedemous; genital 

 pores at XI-XII and XII a 2 /a 3 ; color green with three series 

 of pale yellow spots. On fishes and free in streams. 



Protoclepsis occidentalis (Verrill) 1874. 



This leech and others of the genus are noteworthy 

 among the members of their family for their transparency 

 and activity. No other glossiphonids creep with any 

 approach to the same speed and none swim so well. So 

 far as has been observed the eastern species is exclusively 

 sanguivorous, pursuing and attacking frogs and fishes. 

 Nothing is known of the breeding habits beyond the fact 

 that spennatophores are formed and attached to the skin. 



FIG. 999. Protoclepsis occidentalis. Dorsal view of anterior 

 seven segments, showing annuli, eyes, and sensillae. X 20. 

 (Original.) 



Complete somites not triannulate 29 



Complete somites of two annuli, the anterior much the larger. 

 Salivary glands compact; gastric ceca seven pairs; epidid- 

 ymis a short, wide, U-shaped sperm-sac; eyes one pair, 

 united; genital pores separated by the large annulus of 

 XII; size small. On salamanders, North Carolina. 



* Oligobdella biannulata (Moore) 1900. 



(* Oltgobdella nom. nov. for Microbdella Moore preoccupied.) 



An interesting and little known leech taken on only one 

 occasion in a cold mountain stream. Nothing known of 

 breeding habits. Color green. 



FIG. 1000. Oligobdella biannulata. General anatomy: boundaries of 

 middle somites indicated; g, salivary gland; at, atrium; Pg, 

 spermatophore sac; 5s, sperm sac; $ male and 9 female orifices; 

 c\ to c 7 , gastric ceca; ov, ovary; vd, vas deferens; ti to k, testes; i, 

 intestine; a, anus. X 10. (After Moore.) 



