;41g PROCEEDINGS OF THE NATIONAL MUSEUM. vol.38. 



where the bone joined the nuchal and where it joined the second 

 peripheral. The free border is obtuse. On the upper surface are 

 seen part of the firsl vertebral scute, a part of the first costal scute, 

 and parts of the first and the second marginal scutes. The ascending 

 plate of <>ue of the bridge peripherals is penetrated by the extremity 

 of a rib. 



Fig. 17 presents a view of the left seventh peripheral. Its length 

 near the free border is 7.3 mm.; its height is 96 mm. The free border 

 is subacute. The front border is greatly thickened, to form a shoul- 

 der to receive the inguinal buttress of the plastron. This buttress 

 did not rise to the lower borders of the costals. On the upper part 

 of the inner face of the bone is a shallow groove in which lay the end 

 of the rib of the fifth costal plate. Farther down this rib enters the 

 bone and descends a distance of 44 mm. from the upper border. 



Of the plastron there are present a fragment of the right xiphi- 

 plastron ami the portion of the hypoplastron that sends up the right 

 inguinal buttress. Fig. 18 represents a section taken just behind 

 this buttress. It shows the thickness of the bone and the form of the 

 free holder at the base of the hinder lobe. The underside of the 

 fragment shows the outer end of the abdomino-femoral sulcus. The 

 xiphiplastron is quite thin, the thickness just behind the femoro-anal 

 sulcus being only (i mm. The free edge is acute. The sulcus just 

 named is directed forward as it moves toward the midline. 



The outer surfaces of all the bones, those of the plastron as well as 

 those of the carapace, are ornamented with shallow pits arranged in 

 more or less regular rows. The rows are directed obliquely to the 

 sutural borders of most of the bones (Plate 11, fig. 3). There are 

 three lows of pits ill a line 5 mm. long. The ridges between the pits 

 are rounded on their summits and the cross ridges are feeble. 



This species is evidently different from all of those decribed from 

 the eastern region of the United States. From A. lineolatus, the 

 type of which came from Colorado, the present species differs in 

 having a coarser sculpture, three rows of pits in a 5 mm. line, instead 

 of four or five. 



ALAMOSEMYS ANNEXA, new species. 



The type of this species was found by Mr. J. H. Gardner, of the 

 l'. S. Geological Survey, in the [gnacio quadrangle, La Plata County, 

 Colorado. The exact locality is given as section 1, township 34 

 north, range 8 west. The following note accompanied the specimen: 

 "Turtle bones from the top of the Animas or above." This refers to 

 the Animas formation. Inasmuch as the type of the genus Ahtmos- 

 emys substricta was found in the Torrejon of New Mexico," it appears 



a Mr. Walter Granger, the disco erer of this turtle, informs me that it was found in 

 a dry Band arroyo easl of Escavada canyon. The locality is Dear the southeastern 

 corner of San Juan County, close to the line between this county and what is now 

 Mc kinl<'\ ' 'ounty. 



