SALENIA VARISPINA. 261 



between the Cidaridae and the Echinidae, forming a connecting link between 

 them, combining many features of the Cidaridae proper with true features of 

 the Echinidae, and to consider it as a subfamily of the Cidaridae. The absence 

 of the continuation of the ambulacral tubes through the imbricated scales of the 

 actinal membrane is not an objection to placing them among the Cidaridae, as 

 we find in the Diadematidae similar differences (Diadema and Asthenosoma. 



Salenia varispina 



! Salenocidaris varispina A. Agass. 1S69. Bull. M. C. Z., I. 

 ! Salenia varhtpina A. Agass. 1872. Rev. Ech., Pt. I. 



PL lll.f. s-14. 



The general appearance of this Salenia (PL III. f. S) is that of a young 

 Dorocidaris papilla ta. The primary spines are enormous, twice the diameter 

 of the test in length, of a brilliant white color, and of all shapes. Some of 

 them are uniformly tapering, others swelling at about one third the distance 

 from the base, others flattened and curved, but all finely longitudinally 

 striated and loosely covered with sharp spines, irregularly arranged along the 

 body of the spines. The secondary spines, as well as the greater number of 

 the spines of the ambulacra, as far as the ambitus, are short, club-shaped, 

 sometimes curved and flattened, longitudinally striated with slight serrations. 

 These short spines give to the median interambulacral (PL III. f. 1,.') and 

 ambulacral (PL III. f. 14.) zones the aspect of the corresponding zones of 

 Cidaris ; but they are not, as in Cidaris, arranged in a circle round the base, 

 of the primary spines. These small spines, as well as the whole abactinal 

 area, are covered with prominent, dark violet pigment cells, standing in 

 striking contrast to the white primary spines. The abactinal system has 

 the structure of that of Salenia, but the position of the anal system is that 

 of Htjpomlenia. The imbricated buccal membrane is covered thickly with 

 plates arranged somewhat as they are in Echinocidaris ; the ten buccal plates, 

 placed half-way between test and teeth, are sparingly covered by pedicellaria?.* 

 The primary tubercles of the interambulacral area are large, arranged in two 

 vertical rows in the two areas ; those of the ambulacral area are smaller 

 (PL III f. 10), and diminish rapidly towards the abactinal pole; the median 

 interambulacral space is occupied by two vertical rows of small secondary 

 tubercles. The primary tubercles of both areas are imperforate, but dis- 

 tinctly crenulated. Near the actinostome the ambulacra flare slightly, some- 

 what as in Hemicidaris. The pores are small, placed in pairs far apart, one 



* I could find no pedicellariae upon the test of the single individual coVected. 



