Dr. J. E. Gray on the Box Tortoises. 105 



This makes six species of Calliste now known to inhabit Central 

 America and the Isthmus of Panama, viz. C. larvata from the hot 

 forest-region of the Atlantic side of Guatemala, C. Francescce^ from 

 Costa Rica and Veragua, C. Dowii from Costa Rica, C. Frantzii from 

 the same country, C. gyroloides, a species ranging from Costa Rica 

 to Bolivia, and C. inornata from Panama to the Isthmus of Darien, 



The single specimen of this Calliste now described was procured 

 by Capt. J. M. Dow, Corr, Mem. Z.S., at San Jose, the capital of 

 Costa Rica, during a short visit he paid to that city in the early 

 part of the present year, and by him most kindly presented to me. 

 He was unable to inform me exactly whence it came ; but it was most 

 probably obtained from the low forest-region of the Atlantic slope. 



I dedicate the species to Capt. Dow, whose researches in the ma- 

 rine fauna of Central America are too well known for me to need to 

 dilate upon the justice of the appellation. 



Observations on the Box Tortoises, with the Descrip- 

 tions OF Three New Asiatic Species. By Dr. J. E. 

 Gray, F.R.S., etc. 



The knowledge of the animals of our own country is progressive 

 and only gradually acquired ; and how much more so must it be as 

 regards the species which we receive from a distant country, whence 

 we get only isolated specimens, and often in a more or less imperfect 

 condition, without any account of how they live, and what they eat, 

 and in what manner they conduct themselves ! 



In such cases how can we do more than guess at what is a species, 

 and into what groups the species should be divided ? and yet, because 

 we doubt in what we are doing (and the older we become in the 

 study, the more do we see the necessity for doubting, and the more 

 do we see the imperfection of our materials) — yet, on the doubts 

 which arise from such causes and not from any want of faith in the 

 principle that species are permanent, if we only had materials enough 

 to study them properly, do theorists wish to support the theory that 

 species gradually pass into each other, and have been derived, or 

 rather have originated, from such transformations. Never was a 

 theory more baseless, as far as our knowledge is concerned. 



This imperfection of our knowledge is specially the case with re- 

 spect to exotic Tortoises, of which we sometimes only procure the shell, 

 at other times the animal with the shell in a more or less perfect 

 condition ; and when the latter is procured, we find that the conclu- 

 sions that we had come to as regards the probable form of the animal, 

 or some part of it, are more or less incorrect, and we are thus obliged 

 to reconsider the situation the species occupies in the series. 



* I had considerable doubts whether this species was really separable from 

 C. larvata, but, having examined a number of skins of both species, have come 

 to the conclusion that the distinction, small as it is, is constant. Dr. Sclater 

 has pointed out in his ' Monograph ' what the differences are, to which I may 

 add that C. Franceses seems a lighter rather than a brighter bird than C. larvata ; 

 the blue on the forehead is a trifle broader in the former ; and the outer bluish- 

 green margin to the middle wing-coverts of the latter is almost obsolete in the 

 former. In fact, there is just a difference, and that is all. 



