On a New Stalked Crinoid from the 



Sagami Sea ((Phrynocrinus obtorlus). 



By 



H. Matsumoto, BigahusH. 



Zool. Inst. Sci. Coll , Tokyo. 



The collector of the Misaki Marine Laboratory, Mr. K. Aoki, 

 obtained a specimen of an interesting stalked Crinoid at Okinose in 

 the Sagami Sea on Jan. 14., 191 2. Though unfortunately the greater 

 part of its crown had been broken off and lost, the curious structure of 

 the stem at once attracted my attention, and on a close examination it 

 was found that this crinoid is evidently referable to Phrynocrimis * 

 CLARK, but that it represents a second and new species distinct from 

 the genotype. 



Phrynocrimis obtortus, n. sp. 



The stem, completely preserved, measures 320 mm. in length and 

 is composed of columnals just one hundred in number. These in 

 lateral view presents each a somewhat trapezoidal outline with convexly 

 swollen lateral sides. The external surface of each columnal is divided 

 into four triangular areas by rounded edge-like boundaries, and with 

 the apices directed alternately upwards and downwards. Taking any 

 two consecutive columnals, the upwardly dirceted apices of the triangular 

 areas of the lower one are apposed to the downwardly directed apices 

 of same of the upper. The articular surfaces are elliptical in outline 

 (fig. g), the long (fiderai) axes of the upper and lower articular surfaces 

 not coinciding in their direction but running so as to form certain angles 



* Literature : Clark 1907, two new Crinoids from the North Pacific Ocean. Proc. 

 U. S. Nat. Mus., Vol. XXXII, No. 1543. — Ditto 1910, the phylogenetic interrelationships of 

 the recent Crinoids. Ibid., Vol XXXVIII, No. 1732. — Ditto 1910, on the origin of certain 

 types of Crinoid stems. Ibid., Vol. XXXVIII, No. 1749. 



