ZOOLOGY. 233 
That they are males has been conclusively shown. But what has 
wrought the change? I think it can be shown that lack of nutri- 
‘tion, in consequence of a diminished supply of sap to the leaves, 
has: been the instrument at work. If continuance of warmth and 
consequent plant-vitality are conditions favorable to an almost 
endless succession of the female type, a reverse order of things, by 
acting in a sudden manner, and at a certain stage of female life, 
producing a check to further development, must assuredly gener- 
ate the opposite sex.—T. G. GENTRY. 
A STRAGGLER IN THE On10.—On a recent visit to the Museum 
of Comparative Zoology my attention was called by Mr Bliss to a 
small fish labelled in my own handwriting several years since as 
follows: A singular jish of a rare genus, Louisville, Ky., 1837 
Nothing further is known as to the history of the specimen, but 
as 1837 was some ten years before Professor Agassiz began to 
form the unrivalled collection of fishes to which this specimen 
- belongs, it is very probable that the label was a copy of some older 
one on the bottle in which the fish was received at the Museum, 
simply rewritten by myself sometime between 1856 and 1864. 
On making a careful examination of the fish it proved to be the 
Gobiosoma molestum of Girard, who described the species from a 
specimen obtained by Mr. J. H. Clark at Indianola, on the coast 
of Texas. Girard’s description, with a figure, is in the Mexican 
Boundary Survey (Ichthyology, p. 27, pl. 12, fig. 14), 1859. 
Girard also describes the genus and species in the “Proceedings of 
the Philadelphia Academy,” 1858, p. 169. The description by Girard 
applies perfectly to the Louisville fish and his figure is nearly cor- 
rect. Inote the following slight differences. Girard’s specimen was 
two inches in total length, the Louisville specimen is two and one- 
half inches ; Girard gives the fin rays as follows; dorsal vir+-12, 
anal 11, ventral 5, pectoral 16, caudal 20. My count of the 
Louisville specimen is, dorsal vi1-+12, anal 12, ventral 1+-5, 
pectoral 18 or 20, caudal 20; so that there is no important va- . 
tiation, Ventral 5, as given by Girard is probably a mistake due 
_ to his overlooking the small ventral spine which is common to 
nearly all members of the family. The proportions of the two 
fishes are the same. Girard’s figure represents the rays of the first 
~ dorsal a little too far apart and the last rays are too short, as there 
_ ks but little, difference in the length of the rays of this fin. The 
