The Soft- shelled Turtles 



THE BROWN SOFT-SHELLED TURTLE; OR UNARMED 

 SOFT-SHELLED TURTLE 



Trionyx muticus, (Lesueur) 



From the two preceding species,* this soft-shelled turtle 

 differs in the absence of spiny tubercles on the front margin of 

 the carapace. It is also of smaller size and the head is pro- 

 portionately narrower. 



Colouration. The head markings are like the Spiny Soft- 

 shelled Turtle the bands uniting at the base of the proboscis; 

 on many specimens the head markings are very obscure. 



The carapace is brown or olive, and with but faint mark- 

 ings. They may be in the shape of short, line-like spots, or 

 dull blotches. 



Dimensions. The smallest of the North American species, 

 seldom attaining a length of shell of over ten inches. The meas- 

 urements of a specimen taken in the Mississippi River, near 

 St. Louis, Mo., are given: 



Length of Carapace 6| inches 



Width of 6 " 



WidthofHead | " 



Distribution. Central and northern tributaries of the 

 Mississippi River and tributaries of the St. Lawrence. The 

 species is not so widely abundant as the Spiny Soft-shelled Turtle. 



EMORY'S SOFT-SHELLED TURTLE 



Trionyx emoryi, ( Agassi z) 



Though this species is closely related to the Southeastern 

 soft-shelled turtle, (T. ferox) there are no tubercles on the front 

 margin of the carapace. The proboscis is rather short. 



Colouration. Carapace olive, with the usual, pale margin. 

 In place of the ring-like markings of the allied species, there 

 are numerous black dots. 



The head markings appeal to those of ferox. The pale 

 lines unite in front of the eyes, but they fuse into a pale, trian- 



* It must herewith be explained that the arrangement of the species 

 is not according to technical classification, but in a fashion that will be 

 most readily comprehended by the less advanced worker. In reality, 

 T. muticus is most nearly allied to T. spinifer and should thus follow it, 

 while the same condition relates to T. ferox and T. emoryi. 



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