334 Miscellaneous. 
seems conceivable that a spermatozoon of an earlier male, which 
was for any reason unable to produce a perfect embryo, might enter 
an ovum without destroying it or causing it to develop, and that 
the ovum might afterwards be fertilized by a perfect spermatozoon 
of another male, and develop accordingly. The germ-plasm derived 
from the first and apparently ineffectual spermatozoon would account 
for the result as recorded, and the hybrid or mongrel animal would, 
in fact, have two fathers. 
This is hypothetical, of course; but, while waiting for further 
proof, it may be permissible to set hypothesis against hypothesis. 
T. D. A. CockERELL. 
Las Cruces, New Mexico, U.S.A., 
Aug. 3, 1893. 
On the Identity of the “ Cotton Spinner” (Holothuria nigra) of 
English Authors with Holothuria Forskali, Chiaje, and on the 
Occurrence of Cucumaria Koellikeri, Semp., in the Atlantic Ocean. 
By Dr. Emin von MaRenzeLLer. 
The following observations were evoked by the examination of 
certain Holothurians which were collected off Sines, on the coast of 
Portugal, and for which I am indebted to the kindness of Prof. 
Paulino dOliveira, of the University of Coimbra. The collection 
comprised specimens of Holothuria Forskaliz, Chiaje, Cucumaria 
Koellikeri, Semp., and Cucumaria Montagui, Flem. 
Holothuria Forskalii (to which species Ludwig justly assigned 
HT. cataniensis, Gr.) was first shown to exist in the Atlantic Ocean 
in the year 1882 by Greeff. The author referred to found the 
species in Setubal Bay, while in 1890 Hérouard reported it as 
occurring at Roscoff. This Holothurian, which is characterized by 
its external appearance, by the slight development of the calcareous 
bodies, and the possession of Cuvierian organs, had, however, 
already been observed long before on the British coast, especially 
in the West of Ireland, and had been designated ‘the Nigger 
or Cotton Spinner” (Holothuria nigra). Anyone may convince 
himself of the justice of this view by comparing the calcareous 
bodies of H.'Forskalii with the figures of these structures in H. nigra 
given by Jeffrey Bell (‘Catalogue of the British Echinoderms,’ 
London, 1892). For my part I was also able to compare prepara- 
tions of calcareous bodies furnished to me by the Rev. Canon A. M. 
Norman, and derived from a specimen of H. nigra from Polperro, 
Cornwall. That this state of affairs, which is interesting from the 
point of view of animal distribution, remained so long undiscovered, 
is probably to be ascribed to the insufficiency of the earlier descrip- 
tions of H. nigra, as well as to the fact that the animals themselves 
did not come into the hands of those investigators who were 
acquainted with H. Forskalii. Moreover, Stichopus Selenke, de- 
scribed by Th. Barrois in 1882 from Concarneau, is certainly nothing 
else than H. Forskalii. The difference shown in the representation 
of the calcareous bodies will receive correction. It appears that in 
