498 A. JEJ. Verrili — Marine Planarians of New England. 



and tubular, often cylindrical or urn-shaped, and capable of being 

 protruded fully from the mouth ; when retracted it lies in the median 

 line, in a definite pharyngeal -cavity. Its base connects with the 

 stomach at the central part from which the three main gastric 

 branches arise. 



Two of the main gastric branches run backward, one on each side 

 of the pharyngeal and reproductive regions, and from these numer- 

 ous smaller transverse branches, either simple or branched, run out 

 toward the margins, and still smaller transverse branches often run 

 inward toward the center. The anterior main branch is median and 

 gives off lateral branches more or less symmetrically on each side. 



The brain, frontal nerves, and main lateral nerve-trunks are gen- 

 erally well developed ; a small marginal nerve and a complex nerv- 

 ous plexus can often be distinguished without difficulty. 



The ocelli are often only two, situated over or near the cerebral 

 ganglions, in other cases three pairs, and in many genera they are 

 numerous, in tw^o groups ; sometimes they are lacking. A median 

 otocyst is sometimes present. 



The species are nearly all hermaphrodites. There is one common, 

 genital orifice, posteriorly situated. The ovaries, or germaria, are 

 usually two, anteriorl}'^ situated, and special inteUaria are developed 

 along the sides. Spermaries are generally, but not always, numerous 

 and scattered. The copulatory organs present many variations. The 

 eggs are generally enclosed in capsules. Some species are viviparous. 

 Development is direct. 



Most of the species of this group inhabit fresh-water and moist 

 places on the land, but there are several marine genera. The terres- 

 trial species are found chiefly in warm and moist countries, but a 

 single, small terrestrial species [Rhynchodemiis sylvaticus Leidy) 

 inhabits New England, as far north as New Haven, where I have 

 often observed it. 



Famil}^, Bdellourid.e Verrili, 

 Bdelluridea Diesing, op. cit., p. 518, 1861. 



Body elongated, flattened, highly muscular, leech-like, with a well 

 developed posterior acetabulum or sucker. Brain and lateral nerve- 

 trunks well developed ; marginal nerve distinct. Pharynx plicated, 

 cylindrical in extension. Two posterior main gastric branches not 

 united posteriorly. Ectoparasites. 



This family is constituted for the following genus only. 



