258 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



mud; July 30, 1909 (1 large specimen, Cat. Nos. E. 1311, E. 1312, 



U.S.N.M.). 



Station 5641; Buton Strait; Kalono Point (W.) bearing N. 61° 

 W., 3.4 miles distant (lat. 4° 29' 24" S., long. 122° 52' 30" E.) ; 71 

 meters; sand and shells; December 14, 1909 (4 specimens, Cat. No. 

 E. 1270, U.S.N.M.). 



Notes. — The material from station 5137 consists of two specimens 

 with fusiform spinous primaries, and in addition a few detached 

 spines. There are 2 young specimens from station 5145. From sta- 

 tion 5151 there are 2 rather small specimens with fusiform spinous pri- 

 maries, one of them with a parasitic gastropod (Mucronalia) at the edge 

 of the peristome. The specimens from stations 5160, 5174, and 5355 

 are all young. The 2 specimens from station 5481 are large and old; 

 the larger is 80 mm. in horizontal diameter, with cylindrical primary 

 spines which are overgrown with barnacles and sponges. The speci- 

 men from station 5482 is large, with cylindrical primary spines. The 

 4 specimens from station 5641 partly have the primaries fusiform and 

 strongly spinous at the base. (Pis. 53, 54.) 



Remarks. — It is very tempting to distinguish as a separate variety 

 the form which has the primary spines fusiform and strongly spinous 

 in the basal portion (on the aboral side only) , as its general appearance 

 is very characteristic and very different indeed from that of the form 

 with cylindrical spines. But so many transitional forms are met with 

 and sometimes found together in the same locality (as for instance at 

 station 5641) that no line of demarcation can be drawn between them, 

 and we are thus forced to accept them as belonging within the varia- 

 tional range of the highly polymorphous variety annulvfera of the 

 highly polymorphous species Prionocidaris baculosa. The various 

 forms are bound together by that eminently characteristic pecul- 

 iarity, the red-spotted collar of the primary spines, which is other- 

 wise nowhere met with among cidarids excepting, to some degree, in 

 Stylocidaris bracteata (A. Agassiz). 



PRIONOCIDARIS BISPINOSA (Lamarck) 



Plate 52, fig. 3 



Phyllacanthus annulifera A. Agassiz, Illustr. Cat. Mus. Comp. Zool., No. 7, 



pt. 3 [Mem. Mus. Comp. Zool., vol. 3], 1873, p. 387. 

 Rhabdocidaris bispinosa de Loriol, Mem. soc. sci. nat. Neuchatel, vol. 5, 



1873, p. 33, pi. 5. 

 Leiocidaris bispinosa Doderlein, Jenaische Denkschr., vol. 8, 1902, p. 695, 



pi. 58, figs. 5-11. 

 Cidaris (Siephanocidaris) bispinosa de Meijere, Die Echinoidea der Siboga- 



Exped., 1904, p. 4, pi. 1, fig. 4; pi. 2, fig. 14. 

 Prionocidaris bispinosa Doderlein Abhandl. Senckenb. naturf. Ges., vol. 34 



1911, p. 240, pi. 9, figs. 1, 2.— Th. Mortensen, |Kgl. Sv. Vet. Akad., 



Handl., vol. 58, 1918, p. 6, pi. 3, fig. 1. 



