42 PANAMIC DEEP SEA ECHINI. 



hastigera, varispina, and Pattersoni. As in Salenia Pattersoni 1 the right 

 posterior ocular plate forms with the right posterior genital, the odd genital, 

 and the suranal plate a part of the ring of plates surrounding the anal 

 system, while in 8. hastigera 2 and varispina 3 (PI. 21, figs. 2, 0) the right 

 posterior ocular is excluded from the anal system. In Salenia miliaris, 

 however, the anal system as well as the other plates of the abactinal system 

 are not symmetrically placed as in S. Pattersoni; and in «S'. miliaris, in the 

 youngest specimen examined, 5 mm. in diameter (PI. 16, fig. 2) the right 

 ocular is excluded from the anal system, Fig. 52, but in a specimen of 8 mm., 

 Fig. 58, that plate again forms a part of the plates surrounding the anal 

 system (PI. 16, fig. 4)- A few of the larger plates near the anal opening 

 carry large papillae similar to those of S. padfica figured by Doederlein; 4 

 the other anal plates carry smaller more slender papilla? similar to those 

 of the median ambulacra! area (PI. 15, fig. ;.'). All the plates of the abacti- 

 nal system, exclusive of the anal system, are covered with fixed verrucose 

 papillae irregularly arranged on these plates (Pis. 16, figs. 2, J h 6 ; 17, figs. 

 .?, 3), but far less crowded than in S. hastigera, and showing no trace of the 

 radiating arrangement of the verruca? so characteristic of S. Pattersoni. 

 The ocular plates are in the older stages more elongate (PI. 17, figs. .', 3) 

 than those of S. hastigera, Pattersoni, or varispina. The madreporic body is 

 but slightly developed (Pis. 16, figs. ..', 4. 6; 17, figs. 2, 3). The genital 

 openings are small, placed nearly in the centre of the larger genital plates, 

 and they cannot be traced in young specimens (PI. 16, figs. 2, 4, 6). Salenia 

 ■miliaris is marked for its huge curved spines (PI. 15, figs. /, 2) and the 

 great variation in the height of the test (PI. 14, figs. 5, 8, 11) ; the great 

 length of the primary radioles is very striking; in a specimen 12 mm. in 

 diameter, the longest primary radioles are over 60 mm. in length ; in a 

 specimen 16 mm. in diameter they attained a length of 75 mm. 



A comparison of the fourth and fifth plates of the right anterior inter- 

 ambulacrum in specimens varying from 5 to 13 mm. in diameter seems to 

 show a regular order in the appearance of the miliaries in the angles of 

 the primary coronal plates. In a specimen of 5 mm., Fig. 66, there are 

 three and five miliaries (PI. 17, fig. 5) ; in one of 8 mm., Fig. 67, there are 

 six and six in the same plates (PI. 17, fig. 7); in the next stage of 10 mm., 



1 " Blake " Echini, PI. IV, figs. 3, 15, 18. 



5 " Challenger " Echinoidea, PI. IV, figs. 6, 10, 12. 



8 Revision of the Echini, PI. Ill, fig. 11. 



4 Doederlein, Jap. Seeigel, PI. XI, fig. 9. 



