ODOSTOMIA. 129 



terranean, from 10 to 50 f. (Scacchi and others), the 

 Adriatic (Brusina, as 0. Nagli), the .ZEgean, 7-41 f. 

 (Forbes and Spratt), perhaps the Red Sea (Philippi), 

 and the Canaries, 12-60 f. (M f Andrew). 



"The animal is vivacious, displays the eyes on the 

 march, and makes rapid progression. The head and 

 cloven muzzle nearly resemble those organs in Jeffrey sia 

 diaphana" (Clark, MS.). The front side of the foot is 

 fringed with microscopical and extremely short cilia, 

 which are in a state of incessant motion when the animal 

 is crawling. Brocchi imagined that this species was 

 terrestrial or lacustrine, and belonged to the genus Au- 

 ricularia [Auricula] of Lamarck. The shell is cer- 

 tainly not very unlike Melampus bidentatus. 



It is probably the O. plicata of Fleming certainly 

 that of S. Wood, and the Turboni lla plicata of Loven. 

 Scacchi described and figured it as Rissoapolita. Han- 

 ley called it O. unidentata, myself O. eulimoides, and 

 Leach Alvania Cranchiana. The typical form appears 

 to be the Odontostomia erythraa of Philippi as well as 

 his 0. sicula (cf. Zeitschr. f. Mai. 1849 and 1851). 



N* 41^ 10. O. TJMBILICA'RIS*,(Malm} 



Thirbonilla umbilicaris, Malm, Grotheb. k. Vet. Handl. (new series) no. yiii. 

 p. 128, pi. 2. f. 10. 



SHELL forming a short cone, thin, transparent, and remark- 

 ably glossy : sculpture) none except under a high microscopical 

 power, when some extremely slight spiral striae are discernible 

 in a favourable light : colour clear white, with a very faint 

 bluish tint : spire short, ending in a rather blunt and rounded 

 point, owing to the inversion of the apex : whorls 5-6, convex, 

 very compact, gradually enlarging ; the last occupies three- 

 fifths of the shell ; suture deep, imparting a slightly turreted 

 appearance to the whorls ; owing to the transparency of the 

 shell the periphery of each of the upper whorls appears like a 



* Umbilicate. 



