64 MALONE JURASSIC FORMATION OF TEXAS. [bull. 266. 
linear rays, of which there are 5 to 7 smaller in the shallow-concave 
interval between each two of the larger; a large radial rib ante- 
riorly limiting the area ; preareal surface ornamented with about 40 
strongly elevated concentric ribs which are much finer than those of T. 
rudicostata and between one and a half times and twice as numerous! 
and are separated by intervals prevailingly narrower than them- 
selves. In a specimen smaller than the largest, but which nearly 
corresponds in size with the type of T. rudicostata, there are 15 ribs 
on the lower 10 mm. of height of the valve, as compared with 10 on 
the same part of the height in the said example of T. rudicostatm 
As against 7 ribs included in the lower half of T. rudicostata, there I 
are in one specimen of conferticostata not less than 12, and in another 
14 in the corresponding half. 
Measurements. —The dimensions can not be accurately given. The 
height of the largest specimen is about 33 mm. An apparently 
crushed and abnormally elongated specimen gives approximately! 
Height. 25 nun.; length. 29 nun.: breadth, 15 mm. 
Occurrence. — The species is represented by one nearly complete 
-hell, two considerable portions of valves, and a few fragments; from 
locality 1 \ miles east of Malone station. The shell fragment col- 
lected in L895 by the Messrs. Goodell, and which I referred to in 
volume 5 of the Journal of Geology (p. 817) as ww possibly a Trigonia 
of the section Costatse," is of this species. 
ASTARTID^. 
Genus ASTARTE Sowerby. 
ASTARTE BREVIACOLA Sp. n. 
PI. XI, fig. t. 
Cf. Astarte microphyes Felix. 1891, Beitr. Geol. u. Pal. Mex., j>t. 3, p. 170, PI. 
XXVII. fig. 31. 
The locality H miles east of Malone station yielded frequent ex- j 
amples of this fossil. They agree fairly well with Doctor Felix's 
description of Astarte microphyes, but not with his figure. As 
regards the peculiar disposition of the ribs which is given for A. 
microphyes, the tendency to posterior angular bending is well shown 
in most specimens of the Malone Astarte. but a tendency to anterior 
angular bending is little or in some cases apparently not at all 
expressed. If the Cerro de Titania and the Malone specimens are 
referable to one and the same species, microphyes, as seems hardly 
possible, the form of that species is not quite correctly shown in the 
original figure, as the anterior part of the dorsal line, instead of 
sloping like the posterior part, is strongly excavated just in front of 
the beaks in all of the Malone specimens in which this part of the 
