A. JS. Verrill — Marine Plaiuiruois of Ntv) England. 513 



ones can be seen. Each of these is surrounded at base by a circle 

 of glandular cells.* 



In small speciinjens the male organs are often well developed 

 before the female organs appear. 



According to Professor Mark, the spermatozoa are long and fili- 

 form, thickest in advance of the middle, with a very slender anterior 

 portion, more active and more attenuated than the posterior portion. 



Color usually brick-red or dark orange-red, sometimes pale red, 

 with a central paler spot over the digestive cavity, and usually with 

 a circular or horse-shoe-shaped region of darker brownish red color 

 over the ovaries, and almost entirely surrounding the digestive 

 region, interrupted posteriorly; margins pale; caudal cirri translu- 

 cent, whitish; ventral surface yellowish. 



The orange coloi*, according to Professor Mark's observations, is 

 due to clusters of two kinds of minute pigment-corpuscles. Of 

 these, the most numerous are greenish yellow; the others, which are 

 smaller and less numerous, are purplish. The pale median patch is 

 caused by whitish, mostly rod-like, corpuscles. Clusters of cigar- 

 shaped rhabdites are also scattered in the integument. 



Length 3 to 4'"™; breadth 1-5 to 2"'". 



Common from Great Egg Harbor, N. J. to Casco Bay, Me.; espe- 

 cially in sheltered harbors, adhering to eel-grass [Zostera) and creep- 

 ing over the vegetable debris, shells, etc., on the bottom in shallow 

 water, where it is often extremely abundant. 



I have taken it in large numbers, especially in New Haven Har- 

 bor, 1865 to 1870; Noank, Conn., 1874; Newport, R. I., 1880; 

 Wood's Holl, Mass., 1871, 1875, 1881 to 1887. At Quahog Bay, 

 Me., in 1873, I found it in small numbers, but have not observed 

 it farther north. 



I have been familiar with this species for many years, and have 

 had several drawings and descriptions of it made as early as 1874 

 and 1875, but had put them aside with those of various other Tur- 

 bellaria.f Not knowing that Professor Mark had worked upon 



* Professor Mark (op. cit.) describes some of these " mouth-pieces," observed by 

 him, as filled with the filiform spermatozoa, with clusters of them hanging from the 

 basal portion. He also observed large masses of, spermatozoa in the dorsal cavities 

 of the spermatheca, with which the "mouth-pieces" communicate. The vagina ter- 

 minates in proximity to the dorsal cavities of the spermatheca. 



f In the summer of 1874, while in charge of the invertebrate zoology of the U. S. 

 Fish Com., at Xoank. Conn , I had the pleasure of studying this species in company 

 with the late Professor Joseph Leidy, who was much interested in its anatomy. P'or 

 that reason in my MSS. notes I had named it in honor of Professor Leidy. 



