POURTALESIA MIRANDA. 139 



plate, also limited to the plates of the odd interambulacrum (Pis. 58, 6g 4; 

 59, fig. 3). 



Station 3111, between Bindloe and Wenmam Isds., Galapagos, in 1189 

 fathoms. Lat. 54' N.; Long. 91° 9' W. Bott. temp. 36°.2. Yell. glob. ooze. 



Station 3431, off Altata, Gulf of California, in 995 fathoms. Lat. 23' 

 59' N. ; Long. 108 40' W. Bott, temp. 37°. Light br. m. glob. 



Bathymetrical range, 995-1189 fathoms. Temperature range, 37°-36°.2. 



Pourtalesia nriranda A. Ag. 



Pourtalesia miranda A. Ag. 1 Bull. M. C. Z. 1869, I, No. 9, p. 272. 

 Pourtalesia miranda A. Ag. Rev. Echini, 1872, p. 345, PI. XVIII. 



In 1878-79 the "Blake" collected at two localities fragments of Pourta- 

 lesia miranda 2 from which it has been possible to give details of the species 

 and compare it with the other species of the genus. 



Owing to the small size of the P. miranda collected by Pourtales, 3.5 mm. 

 in length, it was quite possible that it might turn out to be the young of P. 

 Jeffreysi Wyv. Thorn, collected by the " Porcupine. " The specimens of P. 

 miranda collected by the "Blake" in 1878-79 off Grenada in 576 fathoms, 

 with the fragments collected off Barbados, show that this is not the case. 

 The figures of P. Jeffreysi given by Loven 3 show that P. Jeffreysi is propor- 

 tionally much broader, and has a shorter anal snout than P. miranda. The 

 odd actinal sunken groove in P. miranda is longer than in P. Jeffreysi, the 

 sternum of the former is hexagonal, elongated, while that of the latter 

 species is wider. 



In a specimen of P. miranda IS mm. in length the test is more elongate 

 than in P. Jeffreysi, P. laguncula, or in the young specimen figured on PI. 

 XVIII. in the Revision of the Echini. The arrangement of the plates of 

 the test is not shown in those figures. The apical system of P. miranda 

 is compact, Figs. 202, 205. The sutures between the genital plates cannot 

 be made out, Fig. 205. The apical system varies greatly, as in other 

 Pourtalesia? ; Loven figures that of two specimens of P. Jeffreysi* in which 



1 On p. 169 of the Revision, this reference is not correctly given. 



2 The single original specimen of /', miranda collected by Pourtales off the Tortugas in 319 

 fathoms was sent to Frofessor Loven for examination, and unfortunately crushed iu transmission on 

 its vet-urn. 



3 Loven, Pourtalesia, Pis. 1-V. 



4 Loc. cit. PL V, figs. 25-28. 



