POLYCLADS OF W. INDIES AND FLORIDA — ^HYMAN 123 



there are laiown at present six polyclad species common to Florida 

 and the West Indies. Stylochus oculiferus was previously recorded 

 only from the coasts of Florida and North Carolina. 



Indistylochus, new genus 



Definition: Stylochidae of elongated oval form without tentacles; 

 ^vith tentacular and cerebrofrontal eyes; male apparatus with very 

 small prostatic vesticle located ventral to the very large and elongated 

 seminal vesticle; vagina extremely long, slanting forward above the 

 male apparatus, then recm-ving parallel to itself, terminating at the 

 oviduct entrance; Lang's vesticle wanting. 



Type species: Indistylochus hewatti, new species. 



Indistylochus hewatti, new species 



FiGUBES 81, d; 83,a 



Material: Two specimens sent by Hewatt. 



Form: Elongate oval with rounded ends (fig. 81,f/); both specimens 

 had set into a curved shape as shown in figure 81,f/; tentacles absent; 

 margins ruffled; about 20 mm. long by 8 mm. wide. 



Eyes: There is an elongated group of tentacular eyes on each side; 

 between the tentacular groups the cerebrofrontal eyes extend 

 forward as distinct linear groups that, anterior to the tentacular eyes, 

 join and spread anteriorly but do not reach the marginal eyes; there 

 are also scattered eyes lateral to and behind the tentacular groups. 

 The margmal eyes are very small and located close to the margin; 

 they extend, mostly as a single row, around the anterior margin back 

 to about the level of the most posterior of the cerebrofrontal eyes. 



Color: Light brown, white middorsally in life; preserved speci- 

 mens show the usual brown color. 



Digestive tract: Pharynx long and narrow with a number of 

 lateral folds, posteriorly located (fig. 81, d); the mouth was seen 

 posterior to the middle of the pharynx. 



CopuLATORY apparatus: Situated immediately behind the pharynx, 

 near the posterior margin (fig. 81, d). The postpharyngeal part of one 

 specimen was removed and sectioned sagittally. Study of these 

 sections showed that the animal is a stylochid, not a cryptocelid as 

 was supposed from external appearance. A sagittal view of the 

 copulatory apparatuses is shown in figure 83, a. The sperm ducts 

 approach the male apparatus from below and enter, apparently 

 separately, the proximal end of the seminal vesicle. The latter is a 

 large sac of elongated oval form. After receiving the sperm ducts 

 into its narrow beginning, it proceeds forwards for a short distance, 



321696—55- 



