6o RESEARCHES IN HKLMINTHOLOGY AND PARASITOLOGY, 



compressed, whitish, anteriorly attenuated, proboscidiform ; tip 

 recurved, fuHginous, obtuse ; posteriorly broadest, terminating 

 acutely. Eyes two, black, globular, lateral, slightly prominent. 



Length 2 to 5 lines ; breadth at the anterior fourth i-8th of a line ; 

 at posterior fourth, i-4th of a line. 



Habitation. — Beneath stones, flower- pots, and boxes in gardens in 

 Philadelphia, and under fragments of wood, bark, old logs, etc., in 

 forests in the neighborhood of Philadelphia. 



Remarks. — This is the first terrestrial Planaria which has been de- 

 tected in North America. I accidentall}- discovered it first beneath 

 several flower boxes and pots in the small garden attached to my 

 residence in this city, since which I sought for and found it in the 

 hilly woods bordering the Wissahickon creek and Schuylkill river. 

 In its movements it resembles a slug {Limax), and like this leaves 

 behind it a mucous trail. When in motion the anterior portion of 

 the body is much elongated and very narrow, and the portion anterior 

 to the e5^es is recurved. Frequently it raises the anterior third of 

 the body from the ground, moving it from side to side as if in search 

 of something. The recurved portion inferiorly is flat, with the edges 

 often inflected. 



When at rest the body is contracted into an oblong form, and the 

 head lies doubled upon the back. The longest will contract to 2^2 

 lines in length by ]4 a line in breadth, and i-3d line thick posteriorly, 

 and I -4th line wide anteriorh'. 



The coloring matter upon the back is arranged in faint transverse 

 annuli, accumulating upon each side of the middle into a longitudinal 

 line, and a transverse spot about the center. 



The eyes are globular, apparently composed of a vitreous humor, 

 two-thirds enveloped with a black pigment. Thej^ are situated 

 laterally, i-iooth to i-48th of an inch posterior to the extremity of 

 the head, and measure about i-50oth inch in diameter. 



The mouth is inferior and a little posterior to the center. CEsopha- 

 gus keg-shaped, about i-5oth inch long. From the acute tail end is 

 secreted a delicate mucous thread. 



The Planaria appears not to like the water, for although it will 

 live for some hours beneath the surface when prevented from rising, 

 yet it always seeks to leave it and remains out when it has escaped. 



In the same forest localities with the Planaria is found an insect 

 larva, possessing similar habits, which upon careless inspection might 

 be mistaken for it. The movements of the larva are more rapid and 

 vermicular. 



