TESTUDINIDAE 3 5 I 



of marginal shields. The head is covered with smooth skin ; 

 the temporal arch is complete. The limbs are extensively 

 webbed. The tail of the very young is nearly as long as the 

 shell, but it becomes relatively shorter with age, being reduced in 

 the males to about two-thirds, in the females to half the length 

 of the shell. Only two species are found in Europe, the other, 

 E. Uandingi, in Canada and north-eastern U.S.A. 



E. orbicularis s. europaea s. lutaria, the European Pond- 

 tortoise. The shape and coloration of the shell change likewise 

 much with age. In the very young the shell is round, and the 

 shields are rough and slightly keeled, uniform dark brown above, 

 black below, with a yellow spot on each marginal and plastral 

 shield. When half grown the dorsal shields become quite 

 smooth, and are striated or spotted, with yellow upon a dark 

 ground. The head, limbs, and tail are dark, with yellow or light 

 brown spots and small dots. In very old specimens all these 

 yellow marks disappear on the shell, which then becomes uniform 

 brown or almost black. The coloration is subject to much local 

 and individual variation, and there are two main types, the 

 spotted and the radiate. It is difficult to say which of the two 

 is the prettier. One male which I caught in the Aleintejo -was 

 very beautiful. The shell was almost black with a greenish shine 

 when in the water, and had many bright yellow and whitish 

 spots. In the radiate type the yellow is sometimes pre- 

 ponderant, so that each shield becomes a study of delicately 

 painted yellow, brown, and blackish lines radiating from the 

 centre. This variety seems to prevail in the south of Spain, 

 decidedly so in the Marismas, also in Northern Italy, whence 

 most of the European markets are supplied. The largest shell in 

 the British Museum, is 19 cm. = 7^ inches long. Fischer 

 Sigwart received one from Naples which was about 9 inches 

 long, and this seems to have been kept as a pet, since its shell 

 had been gilt. Specimens about 5 inches in length may be con- 

 sidered as fully adult. There are very few reliable observations 

 on the growth of individuals. One of F. Sig wart's grew in 

 eleven years only about 2 '5 cm. = 1 inch, when its shell was 

 13 '4 cm. = 5^ inches long total weight of the tortoise 491 

 grammes, about 1 Ib. One of my own grew from 11 to 13 '2 cm. 

 shell-length, and 8*3 to 10'6 cm. in width within eight years, 

 but this was one of the specimens which, living in a greenhouse, 



