BATOCRINID 2. eller 
Dizygocrinus crawfordsvillensis S. A. M1Luer.* 
1891- Butocrinus crawfordsvillensis, 8S. A. Minter; Adv. Sheets 17th Rep. Geol. Surv. Indiana, p. 64, 
Plate 10, Fig. 11. 
A rather small species. Dorsal cup obconical, truncated at the base, 
nearly one half wider than high, the sides almost straight; the radials and 
brachials marked by well defined angular ridges, following the median line 
of the plates and proceeding to the arm bases; the interbrachials convex, 
covered with obscure radiating ridges. 
Basals short, extended outward and forming a small rim; columnar con- 
cavity deep, occupying one half the diameter of the lower face. Radials 
considerably wider than long. First costals quadrangular, the length equal 
to one half their width ; the second pentangular, of nearly the same propor- 
tions as the first. Distichals two in the antero-lateral rays, followed by five 
palmars, which support the arms. The anterior ray has five distichals and 
no palmars; while in the posterior rays the division adjoining the anal side 
has two distichals and five palmars, and the opposite division five distichals, 
making sixteen arm openings with two arms from each opening, or thirty-two 
to the species (not twenty-four, as stated by Miller). The arms are incurv- 
ing, very delicate, and so short that when recurved they reach but little 
above the summit of the disk. Regular interbrachials three, the first large, 
the others quite small. The anal interradius consists of six plates mcluding . 
the anal; three in the first row, and two in the second. Ventral disk con- 
vex, as high as the dorsal cup, the plates large and tumid. Anal tube nearly 
central. 
Horizon and Locality. — Keokuk limestone; near Crawfordsville, Mont- 
gomery Co., Ind. 
Type in the collection of Professor Gorby. 
Remarks, — This species resembles Dizygocrinus indianensis, from which it 
differs in the number of brachials, and in the more delicate and much 
shorter arms. 
* We give no figure of this species, as we were unable to obtain the type, and our description is made 
after Miller’s. 
53 
Say 
Fo kapha 
neers ON 
en 
