202 

 5. A Note relating to Procerodes ulvae, P. wheatlandi and G. segmentata. 



By Winterton C. Curtis , Assit. Proffessor of Zoology. Univ. of Missouri, 



Columbia, Mo. U. S. A. 



(Mit 7 Figuren.) 



eingeg. 14. April 1908. 



At the meeting of the American Morphological Society held at 

 Baltimore in Dec. 1900, the writer gave a demonstration of a marine tri- 

 clad collected at Sandwich, Mass. and which was believed to be Ghinda 

 segmentata. The following note appears among the proceedings of the 

 society published in Volume II. No. 6 of the Biological Bulletin. 



»A species of Gunda, which in its external features seemed identical 

 with the G. segmentata of Lang, was found in large numbers at Sand- 

 wich on Cape Cod. The internal arrangement is not, however, as regu- 

 lar as Lang describes for G. segmentata. From a comparison with 

 Verrill's figure of Procerodes ulvae collected in the same region (Trans. 

 Conn. Acad., Vol. VIII, January, 1893) it is probable that the two forms 

 are identical and that Verrill has figured the head incorrectly. « 



Dr. J. Willi el mi has requested me to publish the important parts 

 of the notes and figures made during my study of the fresh specimens 

 of the above mentioned triclad, for the reason that after an examination 

 of all my original memoranda and the specimens preserved from the same 

 lot of material, he believes the form in question to be neither Procero- 

 des (Gunda) segmentata nor ulvae but wheatlandi. Accordingly, I have, 

 brought together in a connected account the notes made during a brief 

 study of the living worms and have placed in Dr. Wilhelmi's hands 

 samples of such permanent preparations as I now have on hand. 



In all, eight specimens were studied alive and examinations made 

 of worms moving freely as well as held under the pressure of a cover 

 slip. Measurements of some specimens gave 4 — 5 mm of length to about 

 1 mm of width, and allowing for some contraction, I considered 5 mm 

 X 3 A mm as accurate an estimate of the proportions as I could make. 

 Examined microscopically, the small transparent specimens are recorded 

 as having spherules of pigment, pink and purplish and others of yellow, 

 others still a bluish green and among them certain colorless spheres. 

 Rhabdites were found distributed in areas which make a polygonal tra- 

 cery on the surface. The larger worms did not show this pigmentation. 

 The shape of the body is indicated by the accompanying sketches (Fig. 

 1 — 6). I studied quite carefully the auricular appendages of the anterior 

 end comparing them with the tentacles shown in Verrill' s figures. 

 These are not tentacles projecting from the dorsal surface of the body 

 near its margin, but projections of the body, though the rolling of the 



