372 0. C. Marsh on the Metamorphosis of 
in each instance—as not unfrequently occurs in nature—some 
of the characters which distinguish the species had already 
preceded them. Among the altered forms, developed from lar- 
vee apparently identical, the two types of coloration, shown 
respectively in figures 3 and 2, have each at present two repre- 
sentatives, and are sufficiently distinct to merit a more particu 
lar description. The former has a ground color of greenish 
black, on which are bands or patches of grayish yellow, more 
or less confluent, especially along the back. The abdomenis 
dusky olive, with a darker medial band. The latter He 
(figure 2) clearly corresponds to Amblystoma maculatum Hal- 
lowell, which is regarded by Prof. Cope as a variety of 4. ma 
vortium Baird. In this torm the ground color is light olive, 
on which are scattered numerous small brown spots, 42 | 
specimen, a few of these first appeared on the tail, and next 
four of larger size on either shoulder, and subsequently other 
on the sides. The specimens of this type are also larger, 
more sluggish in habit than the other variety, and until vay 
recently would have been considered distinct species by all 
herpetologists. In most other respects, however, there 1s little 
or no difference between the two forms, and both of them, with 
one other specimen representing an intermediate grade, must 
apparently all be regarded as belonging to Prof. Baird’s spe 
cles Amblystoma mavortium.* ee 
At the time the Siredons here described were obtained f 
Lake Como, several others also were secured by Prof, Busts a 
Harvard College. All were brought to New York iogehes 
‘there separated, part being taken to Cambridge, where pe oat 
since been carefully observed by Professors Wyman anc. 
and the rest brought to New Haven by the writer. i 
specimens, however, strange to say, have shown but vely” 
just completed its metamorphosis. This individual, as Prof. 
i ; ‘er remaining i 
man informs the writer, seems still to pref ee 
up, and the branchie partially gone. On beim 
ter, it refused food, and soon died. That 
ently this species are occasionally found in wet 
* Journal Acad. Nat, Sci. Philadelphia, 1849, P- 292 
