NO. 5 CLARK : ECHINI OF WARMER EASTERN PACIFIC 323 



of specimens. On the other hand what Mr. Clark calls micropora galapa- 

 gensis is a very well-marked species, not found elsewhere and apparently 

 the only Encope found at the Galapagos Islands. If the tj'pe perspectiva 

 jonesi really came from these islands, it is strange nothing like it occurs in 

 the Velero collection. Its being a bare test debars it from further considera- 

 tion in this report. 



The following key to the eleven species of Encope here recognized 

 will require modification when more material from the Central and South 

 American coast is available. 



A. Unpaired lunule in between the posterior petals for at least most 

 of its length. 



B. Covering of test dorsally made up of rather slender spine- 

 lets the tips of which are swollen but not flat-topped, nor 

 inverted ; cones more or less considerably in contact . 



perspectiva 



BB. Covering of test dorsally made up of spinelets whose tips 

 are more or less evidently inverted cones. 

 Covering of test a fairly smooth pavement of cone-bases 

 loosely in contact; color dark olive-gray . . . wetmorei 

 Cone-bases larger and in close contact, making a very 

 smooth pavement ; petals very large, straight, wide at tip ; 

 color olive-brown or darker with marginal fringe of short 

 brown or reddish-brown spinelets; lower surface brown 



laevis 



AA. Unpaired lunule not forward between posterior petals but more 



or less in line with the posterior lunules or anterior to them. 



C. Lunules usually more or less circular or oval and 



relatively small; test usually less than 120 mm in 



length, commonly about 90-100 mm. Spines of test 



very slender with only slightly enlarged tips . 



. micropora 

 Test covered with the very numerous slender spines, 

 each tipped with an oval ball, commonly white or 



light colored cocosi 



CC. Lunules much longer than wide; test often wider 

 than long. 



