288 [October,- 



1. Emea rubka, Leidy: Pr. A. N. S. v, 125. 



Body contracting irregularly, reddish or yellowish flesh colored. Anteriorly 

 and posteriorly obtusely rounded. Eyes two or three black spots, placed in a 

 line behind one another, upon each side of the head : often irregular. First pair 

 of lateral depressions opposite the interspace of the anterior two pairs of eyes ; 

 second pair just postero-lateral to the posterior pair of eyes. (Esophagus very 

 long and tortuous, villous, furnished at its bottom with a single spine or nail-like 

 tooth, and four others upon each side in a rudimentary condition, enclosed in a 

 sac. Intestine becoming obliterated posteriorly. 



Ordinary length from 1 to 6 lines; breadth from l-8thto l-5th line. Occasion- 

 ally 10 lines long by l-3d broad. 



Habitation. In marshes, ditches, and stagnant ponds in the vicinity of Phila- 

 delphia. 



Variety a. White, 2 lines long; l-6th line broad. 



Habitation. On the under side of stones in the Schuylkill River. 



Remark. I have sometimes met with the largest sized females without the 

 appearance of a developed ovum, and at others, those of from 1 to 3 lines in 

 length, with from 3 to 18 large yellow eggs. 



2. Emea Dugesii, Leidy. 



Polia Dugesii, Qicatrefages : Rech. Anatom. et Zoolog. ii, 211. 



DENDROCGELUM, Oersted. 



Characters same as planaria, with the head furnished with a hemispherical 

 cotyloid cavity, capable of eversion into the form of a pediculated discoidal 

 acetabulum. 



1. Dendroccelum superbum, Girard: Proc. Bost. Soc. Nat. Hist, iii, 265; 

 Keller and Tiedemann, Nordamerik. Monatsb. ii, 2. 



Body thin, plano-convex, translucent white, with the sides nearly parallel ; 

 anteriorly truncated, with the lateral angles slightly projecting; posteriorly 

 obtusely angular. Cotyloid cavity of the head prominent, opening at the anterior 

 truncated margin, when everted presenting the form of a circular disk supported 

 upon a broad columnar contraction of the head. Eyes two, nearly globular, com- 

 posed of a transparent vitreous humour enclosed at the postero-internal half by a 

 black choroid. (Esophagus long, keg shaped ; intestine delicately and minutely 

 ramified, brown or blackish-brown in color. 



Length 3 to 8 lines ; breadth 2-5th to 4-5th of a line. The longest may con- 

 tract to 3 lines by 4-5th in breadth. 



Habitation and Remarks. In ditches communicating with the Delaware and 

 Schuylkill Rivers, below Philadelphia, creeping upon the submerged stems of 

 Arum virginicum, Pontederia cordata, Nelumbium luteum, and Zizania 

 aquatica. 



When seized or irritated it everts its acetabulum, by which it attaches itself to 

 surrounding bodies with the tenacity of a leech. 



