478 A. E. Yerrill — 3Iarine Planarians of New England. 



often in a circular pit ; the female duct is usually elongated and 

 forms a siphon-shaped organ, the longer and narrower leg of the 

 siphon above the vagina, and extending backward into a more or 

 less dilated spermatheca ; the middle portion of the vagina* is 

 thickened and receives, on each side, numerous ducts from the 

 shell-glands. In at least two of our species there appears to be a 

 small posterior genital pore connected with the spermatheca by a 

 narrow duct, somewhat as in Trigonoporus. 



A large, round or pyriform, thick-walled "granular gland" is con- 

 nected with the male organ. Seminal vesicle usually well developed. 

 Penis or verge often long and cirriform. In some species a sucker 

 exists between the genital pores. 



The most obvious distinction between this and the closely allied 

 genera is the unusual elongation of the female ducts and the verge, 

 and the consequent wide separation of the genital pores. The ab- 

 sence of mai'ginal ocelli seems to be constant, 



Leptoplana virilis, sp. nov. 



Plate xlui, figures I, la. 



Description of living specimens : — Body thin, more or less ellip- 

 tical, changeable. Ocelli conspicuous, black, arranged in four dis- 

 tinct, rather large groups, those in the posterior or dorsal groups 

 largest ; the posterior groups are short-oblong or somewhat quadran- 

 gular, divergent, situated near the ganglions, and have each about 

 twelve visible ocelli ; the anterior or cerebral groups are nearly par- 

 allel, elliptical or oblong, a little nearer together than the others, 

 and usually commence between the latter and extend considerably" 

 farther forward over the ganglions ; they consist of man}' minute 

 ocelli and each has a single distinct ocellus, larger than the others, 

 at the posterior, and another at the anterior end of the group. 



Color pale brown covered with darker brown specks and with 

 poorly defined pale blotches. 



Length 18'"'"; breadth 10'^"" in extension. 



Descriptioyi of a specimen mounted in haham : — This specimen 

 (pi. XLiii, figs. 1, la) shows that the ocelli are somewhat more numer- 

 ous than described above, part of them being too deeply seated to 



* The first, or thickened, glandular portion of the duct (r, pi. lxiii, fig. la) is 

 usually called the vagina, but it may not be the copulatory duct, at least in such 

 species as have a second female orifice farther back leading to the spermatheca, as in 

 Trigonoporus. The latter duct, in such cases, is probably the true copulatory duct, 

 the other serving for the laying of the eggs. 



