A CURIOUS MALFORMATION OF THE SHIELDS 
ON. A SNAKE'S HEAD. 
LEONHARD STEJNEGER. 
Dr. Josua LINDAHL, director of the Museum of the Cincin- 
nati Society of Natural History, recently sent me a snake for 
examination which had defied all attempts at identification on 
account of the extraordinary scutellation of the top of the head. 
It was an old specimen found in the basement without label 
and without indication of origin or locality. Its color is entirely 
faded out, the snake is extremely emaciated, and the preserva- 
tion of the body is bad. However, I think I make out 25 
scale-rows, 229 ventrals, a double anal, and about 80 caudals ; 
Lindahl’s measurements are: length, 53 inches; tail, 834 inches. 
The principal feature of the top of the head is the total 
absence of an unpaired frontal, the meeting of the supraoculars 
in a broad suture on the median line, and the extraordinary size 
and shape of the prefrontals. In the suture between the latter 
there is a deep pit filled up with soft skin, and the rostral 
shows some signs of damage by violence. These features and 
the general extraordinary aspect of the top of the head are shown 
in the accompanying sketch (Fig. 2). In all other respects the 
snake appeared to be normal, and while the above-mentioned 
features looked outlandish enough I was soon convinced that I 
had only to do with a most abnormal specimen of the typical 
colubrine snakes. An examination of the dentition and other 
structural characters showed that the specimen belonged to the 
genus commonly known as Co/uder, while the more minute de- 
tails of the scale formula, vzz., one preocular, two postocular, 
two large anterior temporals, in addition to those given above, 
pointed directly to Coluber obsoletus, the common “mountain 
black snake” of the eastern and Austroriparian faunas of North 
America. A direct comparison with specimens of this species 
confirmed the correctness of the identification. For the sake 
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