486 A. E. Verrill — Marine Planarians of Neio England. 



are situated rather far back and are not easily seen in most of the 

 preparations. The male organs consist of a large, elliptical, muscu- 

 lar penis-bulb more or less concealed by a lai-ge round granular 

 gland ; the sessile, rounded or oval seminal vesicle is situated above 

 and partly behind the anterior end of the granular gland ; the penis- 

 sheath is rather long and large, cylindrical or sometimes elliptical ; 

 the penis is, apparently, simple and conical, without a slender chit- 

 inous cirrus. The glandular portion of the siphon-shaped female 

 duct is elongated and dilated anteriorly, in the largest specimens, 

 and extends from near the posterior margin of the body forward to, 

 and often beyond, the male orifice, as seen in tlie best preserved 

 specimens. This region is usually so altered by contraction that the 

 reproductive organs are evidently much altered in form and position 

 in nearly all cases, and therefore vary in different specimens from 

 the same lot. The larger specimens are filled with numerous ovarian 

 and spermarian folicles, and the uterine sacs and \Hi8a deferentla are 

 swollen with their contents. 



Color above, while living, various shades of light brown, often 

 tinged with darker brown in the middle and at the margins. 



Length, in extension, while living, 12 to 16'"™, breadth 4 to 6'"'". 



Provincetown, Mass., 1870, abundant among hydroids, barnacles, 

 etc., on the bottom of a whaling vessel, recently arrived from off the 

 Carolina coast. It was associated with several southern species of 

 mollusks, crustaceans, etc. 



This species is not a typical Leptoplana, but it appears to be 

 closely allied to several foreign species referred to that genus by 

 Lang and others. In its external characters it agrees with the genus 

 Elasmodes of Stimpson, which Lang unites Avith Leptoplana. 



TrigOnoporUS Lang, op. dt., p. 502. 



Pharynx with numerous lateral lobes, stomach with about five or 

 six pairs of main branches, which at first branch arborescently, but 

 distally anastomose more or less completely. 



Marginal ocelli numerous, but minute ; many other similar minute 

 ocelli are scattered over the frontal region. Cerebral ocelli numer- 

 ous, forming large clusters over the ganglions and frontal nerves. 



Dorsal ocelli small and numerous, forming crowded groups, some- 

 times confused with the cerebral clusters. Male copulatory organ 

 with a well developed pyriform penis-bulb and granular gland com- 

 bined ; muscular penis-sheath conical or funnel-shaped ; penis sim- 

 ple, conical ; seminal vesicle apparently wanting. Female duct 



