46 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I45 



Apical system. — Anterior, four genital pores, compact. 



Ambulacra. — Petals well developed, broad, lanceolate, with great- 

 est width one-third distance from apical system to end of petal, all 

 petals of approximately equal length, petals II, IV wider than others, 

 petal III narrower, 43 to 45 pore-pairs in posterior zones of petal II 

 or IV in specimens 54 to 60 mm long; poriferous zones of unequal 



70 -, 



60 



50i 



CO 

 LU 



UJ4Q- 



2 



z 30 



x 



^20 



10 



10 20 30 40 50 60 70 80 



LENGTH IN MILLIMETERS 



Fig. 44. — Rhyncholampas ayresi Kier, new species. Width relative to length 



of test. 



length with one to three more pore-pairs in right poriferous zone 

 of petal II, posterior zones of petals II, IV, and anterior poriferous 

 zones of petals V, I ; single pores in ambulacral plates beyond petals. 



Periproct. — Supramarginal, wider than high, with slight groove 

 extending from opening to posterior margin. 



Peristome. — Anterior, pentagonal, depressed, wider than high. 



Floscelle. — Phyllodes well developed, broad (text fig. 46), approxi- 

 mately 30 pores in each phyllode, with 10 in each outer series, 4-6 



