SPECIES OF MARINE PLANARIANS. 93 



hibited the greatest interest in zoological science, and with great industry and labour 

 compiled the ' Fauna of Liverpool.' 

 Fig. 8. General appearance of upper surface. 



9. Elasmodes obtusus, Coll. 

 Length -fa ; breadth £ inch. 

 Body thin, delicate, smooth, semitransparent, dendritic. 

 Upper surface pale brown, with a dark, shaded brown streak along the middle half of the 



median line, from which radiate delicate pale brown markings, which fade as they 



reach the margin. 

 Under surface pale, and exhibiting the radiating markings, though fainter. 

 Head indistinct. 

 Eye-spots two, somewhat crescentic, situated upon a round, white, transparent space 



immediately in front of the median dark brown streak. 



A very lively, active, and graceful animal. When in motion and fully extended it has 

 a broad or truncated appearance anteriorly. It crawls rapidly, floats feet uppermost, 

 and swims gracefully and rapidly by a vertical movement of the sides of the body, which 

 is performed by quick and sudden jerks. 



One specimen was obtained in Singapore Harbour, west of the town, from beneath a 

 stone between tide-marks, December 3rd. 

 Fig. 9. Upper surface of the animal. 



10. Leptoplana patellensis, Coll. 

 Length \ an inch. 



Body entire, opaque. 



Upper surface cream-colour, smooth, beautifully mottled with rich light brown. A 

 ridge runs along the median dorsal line, irregularly marked with a darker brown, 

 from which the general mottling radiates to the margin, where it is palest. 



Under surface of an opaque whitish colour, the dendritic marking occupying the middle 

 third, of an opaque white, and surrounded with dots of the same. 



Eye-spots irregular and indistinct, consisting of an oval ring at the anterior part of the 

 median line, and on either side an irregular patch, that on the left roundish, and on 

 the right crescentic. These spots when magnified appear roundish, but not circular, 

 and do not present any regular figure. 



This animal moves with a leech-like motion, fixing itself by its anterior and posterior 

 ends alternately. It showed no inclination to swim or float like most of tbe Planarians, 

 nor even to leave the bottom of the vessel of water in which it was contained. 



Two specimens were obtained from under the mantle of a large limpet (Patella oculus), 

 which I knocked off with my foot from the granite boulders of Simon's Bay, Cape of 

 Good Hope, May 23rd. 

 Fig. 10 : a, upper surface, animal in motion ; b, head, enlarged, showing arrangement of eye-spots. 



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