2S4 Mr. E. A. Smith on ihe. 



and Atlantic City, tlie latter in the month of March. Jalginjj 

 from the hopeless way in which it becomes entangle! in th ; 

 sandbanks and shoals of a shallow coast, it would seem to hi 

 unaccustomed to such impediments, and is probably a deep- 

 water species. It is also worthy of note that the Overstraii I 

 Mesoplodon was within a short time of giving birth to a young 

 one, whereas the young of the Hyperood))i are produced in 

 the months of May and June. 



Notwithstanding the very great advance which has been 

 made in our knowledge of the Cetacea of late years, we are 

 still very ignorant with regard to the habits and distribution 

 of many species, and it is most desirable to place on record 

 every circumstance which may tend, even indirectly, to throw 

 light on a subject of so much interest. 



EXPLANATION OF PLATK XV. 



Fit/. I. 3rc«o;;fo(/(>« 6/(7c«s, $, seen from the left side. Scale 1 : 40. Tlie 

 arrow a indicates the position of the blow-hole ; b, gular sulcus ; 

 c, eve ; d, external auditory meatus. 



Fiff. 2. Foetus which belonged to the above specimen, seen from the left 

 and sli<rhtly from the veiitral side. From a photograph taken 

 bj' Mr. \V. D. llarmcr. Scale 1:12. h and c as above; e, right 

 pectoral limb. 



XLVII. — Xote on the Genera Geothauma and Gyrostropha. 

 By Edgar A. Smith. 



The genus Geothauma has recently been proposed by 

 M. Crosse * for the reception of that most wonderful little 

 shell described by Lieut. -Col. Godwin- Austen under the name 

 of Opisthostoma grandiapinosum. M. Crosse considers the 

 trochoid form, the spinous ornamentation, and the manner in 

 which the last whorl is produced upward to the top of the 

 sj)ire of sufficient importance to distinguish it generically from 

 the typical species of Opisthostoma from India. Many of the 

 characters given in the diagnosis of the genus are specific 

 rather than generic. This may have arisen from the fact 

 that M. Crosse appears to have had but a single species in 

 view at the time. At all events, it is unsatisfactory that he 

 has not expressed his views regarding the other known species 

 of 02)ii>thostoina from Borneo, namely 0. d': Crespigniji^ 

 11. Adams, 0. ]Va/lacei\ Ancey, and 0. pulchellum and 



* .Tourn. de Conch. 1892, p. 282. 



