12 Observations on the Terrestrial 



Bethel, Maine ; also found it on the St. John's river at the extreme 

 northern boundary of the State. 



Lingual membrane 90-25-1-25. Central plate long, having one long central 

 denticle and two short denticles. Laterals seven, having one long and one short 

 denticle. Uncini bidentate, aculeate, extreme uncini tridentate. (PI. 5, Fig. VJ.) 



Mr. "W. Thomson in Annals and Mag. N'at. His. second series, 

 Vol. 7, gives the following formula of Vitrina pellucida of England: 

 number of rows 160 ; number in a row 110 ; total 17,600. By 

 the above it will be seen that Vitrina limpida stands thus : number 

 of rows 90 ; number in a row 51 ; total, 4,590. 



HELICELLIN^. 

 Macrocyclis concava, Say. 



Found in several places in Oxford County, though very rare. 

 All the specimens were exceedingly dwarfed. I kept one of this 

 species in confinement with several specimens of Hyalina cellaria ; 

 these it soon devoured, even destroying the viscera far within the 

 shell ; its long cylindrical body being well adapted to facilitate its 

 carnivorous jDropensities. 



I am indebted to the Smithsonian Institution for the use of the 

 cut illustrating the dentition of this species. I solicited the use 

 of it from Prof. Henry in order to complete the dentition of our 

 Maine HelLcellinas. 



Hyalina cellaria, Muller. 

 Occurs rarely in cellars and gardens in the city of Portland. 

 One lady informed me that they troubled her a great deal by 

 crawling into the pans of milk. 



t(j. l». ^^^_^ Buccal plate, (F'kj. 18,) (Fig. 19, yoimgj crescentic, 

 projecting in the centre, forming a well defined point, 

 slightly striate longitudinally in the centre. 



Lingual membrane 38-17-1-17; central plate very 



long and narrow, with three minute teeth occupying 



Fig. 19. nearly the centre of the plate, i. e. midway between 



anterior and posterior edges. First four laterals irregular in shape, apimrently 



bidentate, uncini long, single, aculeate denticles. (PI. 5, Fig. 20.J 



Hyalina indentata, Say. 

 "Widely distributed throughout the State ; more numerous in 

 the interior. 



