No. 6.] BLADDERS OF THE TESTUDEXATA. 297 



box tortoises in freedom as well as in captivity, found that they 

 exhibited great aversion for water when placed in it, and always 

 quitted it as quickly as possible. I have also observed that 

 Terrapene, which is a decidedly terrestrial Emydid and has 

 very rudhiiental "accessory bladders," is very uneasy when 

 placed in water. It is generally believed that they never seek 

 water but live wholly on vegetable matter, and obtain sufficient 

 ?inn ^^— [-— - - -—J 



B 



F„ , - Sections through the bladder ,A ) and the accessory bladder (B) of E,.ys Mandin.ii, 

 showing the epithelial lining of these organs. 



water from this source to mamtahi life. It would seem that 

 the terrestrial mode of life of these tortoises may be an mipor- 

 tant factor in leading to a disappearance of the '< accessory 



bladders." , 1 , 1 -• ^^^ 



Lesueur (lo) again states that the " accessory bladders are 



wanting in the Clieloniidae and Trwnychidac. , ^, , . 



Hoffman (9), too, says they are not present m the Chdom- 



idac but are found in the Chclydidac. He clamis they are 



present in one species of the rnonycladac, but th,s seems 



doubtful since no other investigator is found to support this 



statement. As before stated, I have examined several spec.es 



of aquatic families, Cnostermdac, Tnonyclndac, and Chcl}^rd^e 



and have found no "accessory bladders " in species of the firs 



two families, but they were well developed in three species of 



""ThTa««<«-'"V'"- and THonyMdac are purely aquatic and 

 carnivorous in habit, and rarely go on land except to deposit 

 their eggs in the sand on the shore near the water s edge. 



I quote the following remarks concerning the Che y Ma. 

 from a letter received from Dr. I^ichard Semon : " Chclod.na 



