MUSEUM OF COMPARATIVE ZOOLOGY. 57 



mens the middle row of pores is very irregular, forming zigzag lines, 

 while in younger specimens the middle row is nearly as uniform as the 

 inner and outer rows; the latter is characterized hy the greater size of 

 the inner pore, and the distance separating the pores of a pair. The 

 tubercles of both areas form most regular horizontal rows, as many as 

 ten tubercles of nearly uniform size on each side of the median line, 

 and from one to three for the ambulacral spaces, forming no distinct 

 vertical rows. 



Mus. Copenhague; Mus. Hamburg; Mus. Comp. Zool. — New Hol- 

 land. 



Spatangus Liitkeni.* 



Closely allied to Spatangus purpureus, test relatively more convex 

 and abactinal diameter greater. Seen in profile test nearly semi- 

 circular, somewhat more curved anteriorly ; anal plane lower and more 

 oblique than in S. purpureus, the subanal fasciole belonging properly 

 to the actinal surface. The shape and proportions of the ambulacra, as 

 well as the distribution of the large tubercles between the ambulacra, is 

 not materially different from S. purpureus. The shape of the subanal 

 fasciole (having three pores on each side) is very different from that of 

 S. purpureus (having but two pores) ; it is in the latter species about 

 three times broader than long, while in S. Liitkeni it is only one and a 

 half times broader than long, in specimens of about the same size. The 

 color in alcohol is dark violet. 



Mus. Copenhague ; Mus. Comp. Zool. — China Seas (Salmin). 



Lovenia cordiformis.t 



Differs from the other species of the genus by the great convexity of 

 tile test, the anterior vertex, compared to L. hystrix, the relatively 

 smaller number of primary tubercles in the anterior interanibulacfal 

 spaces, the narrow band of large tubercles upon the edge of the actinal 

 surface, the small size of the purses of these tubercles, the large size of 

 the tubercles within the peripetalous fa>ciole on each side of the anterior 

 ambulacrum near vertex, the flatness of the test round mouth not 

 forming a prominent posterior lip. 



Mus. Comp. Zool. Guayamas ; Smith. Coll. Gulf of California. 



* Sp. altus Liltken MS. in litt. 

 f Liitken MS. in litt. 



