128 AMERICAN JOURNAL 



Terehratula sanguinea, Sby., Thes. Conch, vii, p. 357, pi. 71, 



figs. 71-73 (not of Leach, Lam. nor Donovan). 

 Terehratella sanguinea, Dav., An. Nat. Hist. 1852, p. 368. 



Gray, B. M'. Cat. p. 90. Rve., Con. Ic. pi. vii, fig. 25 a, 



b, c. Journ. de Conchyl. 1861, p. 128. 

 Terehratula pulchella, Sby., Thes. Conch, vii, p. 360, pi. 71, 



fig. 105—107. 

 3fegerlea pulchella, Dav. An. Nat. Hist. 1852, p. 369. 

 Ismenia pidehella, Gray, B. M. Cat. p. 104. 

 Ismenia sanguinea, A. Adams, An. Nat. Hist, ii, 1863, p. 99. 



Hah. Philippines, Sandwich Islands, Japan. Smithsonian 

 Cabinet, 17,820, 17,821. 



This beautiful little species, after having been passed from 

 Terehratella to Megerlia and back again by various authors, has 

 finally found a resting place in the genus Ismenia as restricted 

 by Dr. Gray and Mr. A. Adams. 



There is some variation in the obliquity and breadth of the 

 apophyses in different individuals, but the essential characters 

 remain the same. 



The punctures in the shell are larger and more conspicuous 

 than in any species of the group with which I am acquainted. 

 The imbricating prisms of which the shelly structure is composed 

 are beautifully conspicuous with a very low power, inside ; and 

 even the apophyses seem to exhibit the same or a similar struc- 

 ture, though impunctate. 



The colors vary from almost pure white to a livid red marked 

 with brownish streaks. The normal color is white, with a me- 

 dian line of bright red blotches, bounded on each side by a white 

 streak, outside of which the dashes of red radiate toward the 

 margin. 



The form is usually somewhat transversely oval, and quite 

 regular. The exterior is usually smooth, almost polished, and 

 very slightly marked with lines of growth. Occasionally, how- 

 ever, they are rough, distorted, and of a rude exterior, resem- 

 bling T. ruhicunda junior. 



In general, the foramen is moderate and the deltidia are 

 united, but in many cases the foramen is large, the deltidia are 

 more or less widely separated, and the apex is produced. 



I cannot doubt the identity of T. pulchella, Sby., with T. san- 

 gidnea of Davidson and Chemnitz. 



In the absence of the apophyses this specimen might be con- 

 founded with W. picta and T. rubella. 



The only other recent species is Ismenia Iteevei, A. Ad., An. 

 Nat. Hist. 1863, p. 99. "A large pure white species." Ad. 

 loc. cit. Hab. Gotto, Japan, 48 fathoms. 



