Supplement. 

 PLATE XLIII. 



1 a. Pedina Smithii, Forbes, p. 176. Upper surface, natural size. 

 h. Under surface, natural size, showing the mouth-opening. 



c. Lateral view of the same test, natural size. 



d. Base of an ambulacral area, showing the crowding of the pores in the zones, magni- 



fied four diameters. 



2 a. Hemjcidaris Brillensis, Wriglit (Supplement). Upper surface, natural size. 

 h. Lateral view of the same test, natural size. 



c. Two inter- ambulacral plates, a portion of the ambulacral area, and tAvo poriferous 



zones, magnified three and a half times. 



d. Apical disc, magnified two diameters. 



3. EcHiNOBRissus Brodiei, Wright, p. 353. Upper surface, natural size. 



4. a. Clypeus Plotii, Klein, p. 36L A weathered portion of the upper surface of a 



test of this species, showing perforated tubercles on all the inter-ambu- 

 lacral and ambulacral plates, with the madreporiform body extending 

 over all the pieces of the apical disc, magnified three diameters. 



h. Clypeus Plotii, Klein, a portion of the upper surface of the test, highly magnified, 

 to show the perforations of the tubercles. 



5 a. Heterocidakis Wickense, WrigJd (Supplement). Four rows of plates, natural 

 size. 



b. One of the plates and primary tubercles, magnified three times. 



c. A lateral view of one of the primary tubercles, highly magnified. 



