TESTUDO ELEPHANTOPIJS. 
63 
these animals seems to be sealed : what has been accomplished in the Mascarenes has 
commenced in the Galapagos. 
The specific characters are apparent in mature individuals only. In young examples, 
which are rather common in collections, the distinctive characters, external or osteo- 
logical, are incompletely developed, so that it is, at present, extremely difficult and 
somewhat hazardous to refer very young individuals (up to about 15 inches in length) 
to the species to which they belong. This resemblance of young examples cannot be 
used as an argument against the distinctness of the various species, as generally, in 
Vertebrates as well as Invertebrates, specific characters are not developed before a 
certain period, which varies exceedingly even in groups nearly related to one another. 
1. Testudo elephantopus. 
The Tortoise to which Harlan (Journ. Ac. Nat. Sc. Philad. v. 1825, p. 284) gave 
this name was only 21 inches long over the curvature, or about 17 inches in a straight 
line, and therefore a young animal. A reference to the measurements and figure given 
by Harlan shows clearly that he had an animal with the broad form of the body and 
with a posteriorly truncated sternum — characteristics by which a small series of examples 
before me are distinguished, and more especially one individual of nearly the same size 
as that described by Harlan. 
DuMERiL and Bibron (Erpetol. Gener. ii. p. 115) identify Harlan's example with one 
deposited by Quoy and Gaimard in the Paris Museum under the name of Testudo nigra. 
This specimen is still smaller than Harlan's, and of an age at which the specific 
characters are not yet developed ; and therefore there is no evidence whatever to show 
that this identification by Dumeril and Bibron is correct ; and as long as it is uncertain 
to which of the specific forms the young " T. nigra " should be referred, the name had 
better be disused altogether. Dumeril and Bibron associate with this young specimen 
another of large size, distinguished by its broad form, smooth plates, and posteriorly 
excised sternum, but without giving any convincing proof that these two examples are 
of the same species. I have not seen an example agreeing in all points with that large 
example ; and it may possibly be another species distinct from those described here. 
The materials which I refer to T. elephantopus are the following : — 
1. An adult male example: a perfect skeleton with carapace, but without epidermoid 
plates. The carapace is 31 inches long. History of the specimen unknown; purchased 
of a dealer in Paris for the Oxford Museum, and kindly lent to me by Professor Eol- 
leston, F.E.S. 
2. An immature female example : a perfect skeleton with carapace, but without epi- 
dermoid plates. The carapace is 28|^ inches long. Hah. Galapagos Islands. Property 
of the Royal College of Surgeons. Notes on this example by Professor Owen in 
Rescript. Catal. Osteol. Ser. E. Coll. Surg. i. 1853, p. 194. no. 1011. 
3. Carapace, without epidermoid plates, of an immature male example, 23 inches 
long. History unknown. Property of the Free Public Museum, Liverpool. 
