ClIAP. I. 



GROWTH OF TURTLES. 



295 



tunities of watching it for ten successive years. The other species, of wliich I 

 possess less extensive series, are described in the following, third. Chapter. 



Tiirtk', wlioii liiUcliing, are .ingiilar, when ailiill, 

 rounded; the median ones arc twice as Iiroad as 

 liigli in tiie young ; tliey are as Itroad as high, or 

 even higiicr tlian broad, in the aihilt. GranuhUed 

 in the }oung, tliey are smooth in the uduU. The 

 granulated plate of the first year continues in some 

 hiiiil Turtles, and also in Cistudo virginea, some- 

 times tiiroughout lite, as the centre of the plate. 

 In Chrysemys, and in most Emydoida;, the plates 

 become entirely smooth after the second year. 

 We meet similar discrepancies in reference to tlie 

 plates of the plastron. AVhile in the young they 

 have all the same longitudinal diameter, they arc 

 of very different length in the adult, the three pos- 

 terior pairs, particularly the second pair of the con- 

 necting plates, becoming much higher. All these 

 changes in the form of the plates are, of course, 

 connected with the changes of the general form of 

 tlie carapace, as described above. We find, for the 

 first time, the form of adult plates in specimens 

 about six years old. But I must mention here 

 a remarkable exception, which I once met with 

 in this species, namely, a fine specimen of more 

 tlian seven years exhibiting still all the forms of 

 the plates of the young when hatching. 



We observe similar changes with reference to 

 colors. In Chrysemys picta just hatched, the hack 

 is of a dark gray brown color with a yellow middle 

 line. The marginal plates are red above, each 

 with three semicircular bands, the lowest one the 

 broadest; tliey are red liclow, witii a liiack circle. 

 The plastron is red, in some specimens with a black, 

 bottle-like mark in the middle, occupying the inner 

 margin of all the plates of the plastron. The head 

 is Ijrown, wilii yellow stripes ; a yellow s|iot behind 

 each eye, and a broad, club-like band on each sfde 

 running behind, are particularly conspicuous ; over 

 these there are yellow spots along the neck. Similar 

 bands, forked in front, extend from the angle of the 

 mouth to i\\f fore leg: two other yellow bands are 

 seen along the under-side of the neck ; and finally, a 

 short, imperfect one runs backwards from the middle 



of the lower jaw, not touching the former ones, as 

 in the adult. The fore legs have one red middle 

 slri[)e in front, and another, very short, above it. 

 All phalanges have reddish lines. The hind part 

 of the fore leg is dark brown, with some little white 

 spots. The hind legs iire dark in front, with two 

 yellowish bauds behind, the lower one originating 

 from the base of the tail, where it meets that from 

 the other side, and hence forms one stripe along the 

 under-side of the tail. The tail is marked above in the 

 same way by a yellowish line, forked near the root. 

 In the dress of the Turtle during the second year, 

 there appear entirely new yellow stripes across the 

 back, coloring the anterior margin of the plates and 

 joining the yellow median stripe, which grows then 

 much broader. Moreover, the plastron is no longer 

 red, but yellow. The black mark upon it, if it still 

 exists, extends only from the fourth pair of plates 

 to the last. All the stripes uptm the legs and feet 

 are no longer red, but yellow. In the third year, 

 the colors are brighter, especially the yellow cross 

 bands on the back, which now turn reddish, extend- 

 ing more and more over the nmrgins of the plates, 

 with the exception of the exterior margin. The 

 marginal plates, light red until now, change into a 

 splendid purple. In the fourth year, we see already 

 all thi^ colors of the adult, though the Turtle of this 

 year is not yet half-grown, and though its general 

 roundish form, as well .as the form of the head, of 

 the tail, and of the single plates, still exhibits rather 

 the youthful than the adult characteristics. (Comp. 

 the table above, p. 292.) 



It is interesting to follow out the same develop- 

 ment in another Emydian, Chrysemys Bcllii, which 

 is very nearly related to Chrysemys picta. The 

 organic laws of its development are exhibited 

 in the same way as in Chrysemys picta, but 

 we learn here that the specific character, so far 

 as the coloring is concerned, namely, that black, 

 bottle-like mark, (which we find so largely devel- 

 oped in the adult Clir. liellii, while it is entirely 

 wanting in the adult Chr. picta,) is already very 



