ART. 15 PLEISTOCENE FOSSIL TUETLES — GILMOEE 5 



once raised the question of their specific identity. Fortunately, one 

 of the newly discovered specimens, No. 11,428 U.S.N.M., had the 

 plastral part of the shell preserved so that direct proof of its identity 

 with the type of T . antipex was to be obtained. Both are males, as 

 shown by the concavity of their posterior lobes. No. 11,428 is slightly 

 larger than the type, but with the exception of some minor differences 

 is in such close agreement with it in contour, arrangement, and ex- 

 tent of the plastral scutes, as to leave no doubt of their specific 

 identity. Further substantiation of the identity of T. antipex with 

 T. canaliculata was found in comparing the type lobe of the former 

 with a fragmental portion of the hinder lobe belonging to the type 

 of T. canaliculata. Here again, except for a slight difference in size, 

 the closest resemblances were found. 



At the time of describing T. antipex., Hay * recognized its close 

 relationship with T. canaliculata., but chose to consider them as dis- 

 tinct species for the reasons that in T. antipex " the lateral keel is 

 much more conspicuous, the free borders of the peripherals are more 

 strongly recurved, and the shell is still thicker and heavier." It 

 will be observed that all of the differences noted are those of degree, 

 and well represent the variations in structure to be found within the 

 species; in fact, such differences are noted in a comparison of the 

 specimens now before me. 



Description. — Tlie description to follow of the shell structure of 

 Terrapene canaliculata is based upon the following new materials: 

 No. 11,428 U.S.N.M., a nearly complete carapace and plastron col- 

 lected by Dr. J. W. Gidley in 1926 on the " Golf Course Locality," 

 2 miles west of Melbourne, Brevard County, Fla., from Sellard's 

 No. 2 level; No. 11,330 U.S.N.M., a carapace in two disconnected 

 parts; the complete right anterior fourth extending across the 

 midline and the complete left side and rear past the middle, collected 

 by Dr. J. W. Gidley, near Sellard's locality (Sellard's level No. 2), 

 Vero Beach, St. Lucie County, Fla. ; No. 25-144 Amherst College, a 

 complete carapace collected by Dr. F. B. Loomis at Vero, Fla., from 

 Sellard's No. 2 level; No. 25-145, A.C., a nearly complete carapace 

 collected by Dr. F. B. Loomis, from the bank of the canal, 1 mile 

 north of the center of the town of Melbourne, Brevard County, Fla. 



Primarily the description to follow is based upon the best pre- 

 served specimen. No. 11,428 U.S.N.M., although much supplementary 

 information is furnished by the other specimens enumerated above. 

 All of the specimens are fully adult individuals having the bones 

 of the shell so firmly united that the forms of the neural, costal 

 and peripheral bones are largely unknown. A few costal and 

 peripheral sutures can be detected in specimen No. 11,330 U.S.N.M., 



« Eighth Ann. Rept. State Geol. Survey of Florida, 1916, p. 61. 

 48181—27 2 



