POLYCLADS OF THE EAST COAST — PEARSE 77 



ed, it measured 22.5 by 12.7 mm. It was collected near Cobourg Is- 

 land, Baffin Bay, August 13, 1935, by Capt. Robert A. Bartlett. A 

 specimen found among ascidians on piles in St. Joe Bay, Fla., on 

 March 28, 1936, measured 26 by 6 mm when alive and crawling ; pre- 

 served and mounted, it measures 13.8 by 5.3 mm. Four other speci- 

 mens were taken in this locality. I collected one specimen at Beau- 

 fort, N. C, during the summer of 1938. 



Genus STYLOCHOPLANA Stimpson 



STYLOCHOPLANA FLORIDANA, new species 



Figure 27 



Many specimens of this polyclad were collected ; two on November 

 21, 1935, and others in February and March 1936 in old shells from 

 Crooked Island Sound and St. Joe Bay, Fla. Wlien alive these were 

 active and moved about, often making quick j erics of their margins. 

 When disturbed on the surface film they quickly darted to the bottom 

 of the dish, like a wriggling fish. They had a delicate greenish tint. 

 Many individuals appeared to be immature, as there were no eggs in 

 the uteri, but in March some individuals laid eggs in the laboratory, 

 and some of this group measured 8 by 3 mm when crawling and ex- 

 tended. Preserved, stained, and mounted the largest individual meas- 

 ures 6.4 mm long and 2.6 mm wide. The blunt, rounded anterior end 

 in front of the brain is the widest part of the body ; the posterior end 

 tapers to a point. Various organs are the following distances from 

 the anterior end : Brain, 1.3-1.6 mm ; tentacles, 1.4-1.6 mm ; pharynx, 

 2.0-3.5 mm; mouth, 3.1 mm; seminal vesicle, 3.6 mm; genital opening, 

 4.2 mm; accessory bladder at posterior end of vagina, 4.3 mm. The 

 pharynx is narrow (0.6 mm) and arranged in about 10 folds on each 

 side. The lateral enteric caeca do not appear to anastomose. There 

 are five or six pairs, and a median anterior caecum. The gut of one 

 of the specimens collected contains a small polychaete worm, and an- 

 other had eaten the posterior portion of a copepod. An individual 

 examined alive on February 10, 1936, spit out some encysted proto- 

 zoans, which contained red pigment spots and looked like euglenoids. 

 The tentacles are about 0.1 mm long and bear five or six eyes. Six 

 eyes lie on each side anterior and lateral to the brain and five on each 

 side between and posterior to the bases of the tenacles. 



The globular seminal vesicle lies close to the posterior border of 

 the pharynx. It connects with a long (0.3 mm) tube that bears pros- 

 tate glands and leads to the penis, just anterior to the genital opening. 

 The vasa deferentia are to be seen coiled on each side at the posterior 

 end of the pharynx for a longitudinal distance of about 1.5 mm. 



