254 
The Ohio Naturalist. 
[Vol. V, No. 3, 
task before collectors is to show whether this territorial gap can- 
not be filled in; and if it is filled in, to ascertain whether the 
southern specimens have even a varietal difference from the 
northern type rixosiis. The crowding of the mandibular incisors 
so that the second one is forced to take a position posterior to the 
others, which has been noted in some of the southern specimens, 
“can be found in many examples of any species”* and accord- 
ingly cannot be diagnostic of any one. Unless some substantial 
difference is found, the name allegheniensis will ultimately have 
to retreat, and all the specimens be called rixosus. 
However, while this task is in progress, we may very properly 
make the most of this rare and beautiful addition to our local 
fauna, and let the designation stand as allegheniensis. 
* Bangs, loc. cit. p. 12. The second lower incisors are so displaced in the Oberlin 
specimen . 
Oberlin, O. 
A LAND PLANARIAN IN OHIO.* 
L. B. Walton. 
The Land Planarians form a subdivision of the class Turbel- 
laria which together with the Trematoda (parasitic flukes), and 
Cestoda (tape worms) constitute the phylum Platyhelminthes or 
flat worms. With a very few exceptions the planarians living a 
terrestrial life are tropical forms, only 7 of the 348 species now 
known to science being found in the palaeartic (European sub- 
region) and neartic regions. Of these a single species, excluding 
Platocephahis kewensis an introduced form occuring in hot houses, 
has been described from the United States. This species, 
Rhynchodemns sylvaticus, was established by Leidy in 1851 based 
on five specimens collected in Philadelphia. 
The occurence of a species of Rhynchodemus at Gambier, 
Ohio, differing in many particulars from the form to which Leidy 
called attention i« in consequence of considerable interest. Five 
representatives of this species were found on the partially decayed 
stem of a Virginia creeper July 9, 1904, near Bexley Hall. A 
somewhat more extended study and a comparison, if possible, 
with the type of R. sylvaticus will undoubtedly show the relation- 
ship between the two forms. 
* Read before the Ohio State Academy of Science, Nov. 26, 1904. 
Kenyon College, Gambier, Ohio. 
