MUSEUM OF COMPARATIVE ZOOLOGY. 41 



its nucleus which, though small, is swollen and set on the peak of a very acute 

 spire like a swollen terminal bud on a twig. In delicatus the nucleus, instead 

 of appearing larger, is considerably smaller than the whorl in front of it, in 

 which it is also partially immersed. 



Actaeon delicatus n. s. 



Plate XVII. Fig. 5. 

 Actceonfasciatus? Dall, Bulletin M. C. Z., IX. p. 94, 1881, not of Lamarck. 



Shell ovate, white, or suffused with rose pink, not in bands but generally, or 

 in longitudinal flammules, with usually a white margin in front of the suture ; 

 there are six or seven whorls, the last more than half the length of the shell, 

 regularly rounded and grooved by, on the last whorl, 20-30 strong, rather 

 deep, coarsely punctate grooves between rounded interspaces ; lines of growth 

 quite perceptible, suture somewhat appressed, not channelled ; aperture more 

 than half as long as the shell; outer lip thin, inner lip hardly callous, colu- 

 mella straight, without any chink behind it, and bearing a single moderate fold. 

 Nucleus small, mostly immersed in the succeeding whorl, apex not acute, 

 surface usually not polished but a little less coarsely sculptured than that of 

 A. Cumincjii Adams. Lon. of the largest specimen, 10.0; max. lat. 5.6; 

 Ion. of aperture, 6.0 mm. 



Habitat. Station 19, 310 fms. ; by Sigsbee, Station 50 (Lat. 26° 31' and Lon. 

 85° 53' W.), in 119 fms.; Station 290, off Barbados, in 73 fms., coral, bottom 

 temperature 70°.75 F. ; and Station 100, off Morro Light, Havana, in 250- 

 400 fms. 



The difference between the nucleus of this species and that of A. Cumingii 

 is noted under the latter species. It is just possible that it is to the present 

 species that is to be referred the single specimen obtained by Gabb, and which 

 he referred to A. tornatilis. The latter is not known from this region. 



Acteeon melampoides Dall. 



Plate XVII. Fig. 2. 



Actceon melampoides Dall, Bull. M. C. Z., IX. p. 95, 1881. 



? Actceon hebes Verrill, Trans. Conn. Acad., VI. p. 428, pi. xliv. fig. 15, 1885. 



Habitat. Station 19, 310 fms., off Bahia Honda, Cuba, bottom temperature 

 52°. 5 F. Station 2224 of the U. S. Fish Commission, in 2574 fms., off the east 

 coast of the United States (Verrill). 



I have not seen the typical specimen of A. hebes, but the figure and description 

 agree so closely with A. melampoides that I have little doubt of their identity. 



Only one specimen was obtained by the Blake. 



Among Antillean shells I have seen nothing which I could identify with the 

 A. splendidulus of Morch from St. Thomas, or the biplicate Cuban A. ovulum 

 Pfr. The last is only 1.6 mm. long, and may be an immature Marginella. 



