A LAND PLANARIAN WITH AN ABNORMAL NUMBER 



OF EYES. 



L. B. Walton. 



The land planarians which are relatively common in the 

 tropical regions have few representatives in the temperate zones, 

 only two species thus far being known from America north of 

 Mexico, with the exception of the introduced form, Placocephalus 

 kewense (Moseley) occurring in the hot houses. These are Rhyn- 

 chodemns sylvaticus (Leidy) and Rhynchodemus atrocyaneus Wal- 

 ton, the latter represented by only two specimens and the fonner 

 by ten specimens all belonging to the collection of the Department 

 of Biology, Kenyon College. It is therefore of interest to record 

 a specimen belonging to the former species which possesses two 



Y \^ 1. Rhynchodemtis sylvaticus (Leidy). A Land Plaiiaririn from Ohio 

 with an almormal pair of eyes. A. Entire individual .^lightly contracted 

 (xlO). B. Head showing relative .size of eyes (x2o). 



pairs of eyes instead of the normal single pair. The individual 

 was am.ong five collected July 4, 1904 under the i)artially decayed 

 stem of a Virginia Creeper — Ampelopsis qi<iiiqi(cJ'olia, and the 

 peculiarity was not noted until sometime later when cleared in 

 cedar oil prc])aratory to sectioning. 



The two pairs of eyes are nearly nomial in position, the anterior 

 pair being ().2() mm. and the posterior pair 0.33 mm. from the tip 

 of the head in the preserved specimen fixed in hot sublimate 

 alcohol (Apathy) and sotnewhat contracted. The anterior pair 



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