54 ECHINODERMA OF THE INDIAN MuSEUM, PART VII. 



by a strong transverse ridge ; always five basals ; arm bases occupying the 



entire distal border of the radials. 



d' stem terminating in a large heavy terminal plate ; basals very small, 

 triangular, barely in apposition laterally ; at least eleven brachials before 

 the first axillary ; lowest pinnule on the fifth brachial {i.e., anterior to 

 the first axillary). 



I'HRYNOCRINID^, p. 273. 



(Cf. key 26.) 



d' stem terminating in a diffuse branching root; basals large, trapezoidal, 

 closely united or fused laterally ; rays dividing on the second post-radial 

 ossicle, or not at all ; no pinnules anterior to the first axillary. 



BOURGUETICRINID.E, p. 274. 



(C/. key 27.) 

 7. — Key to the Subfamilies of Comasterid^e. 



a' The distal segments of the cirri bear dorsal processes; the segments of the 

 genital pinnules are not especially short nor broad. 



b' ten or more arms ; if the latter, the division series are all 2, or the IIBr 

 •series are 4 (3-|-4), the following 3 (2-1-3), and the first syzygy is, at least 

 on the inner arms, between the first and second or second and third (never 

 between the third and fourth) brachials. 



CAPILLASTERIN/E, p. 68. 



b* always more than ten arms ; some or all of the IIBr series 4 (3-(- 4) ; following 

 division series 4 (3-|-4) or 2 ; a syzygy always occurs between the third and 

 fourth brachials of the free undivided arms. 



COMASTERIN^, p. 83. 



a* cirrus segments always smooth ; segments of the genital pinnules very short 

 and broad, more or less produced distally ; rai-elv more than ten arms ; IIBr 

 series, when present, always like the IBr series, and united by p.seudo-syzygy , 

 appearing externally as if united by a true syzygy. 



COMACTINIIN^, p. 78. 



8. — Key TO THE Genera of Comasterid^. 



a' Elements of the IBr scries and first two brachials united by pseudo-syzygy, not 

 differing externally from a true syzygy ; rarely more than ten arms ; IIBr 

 series, when present, similar to the IBr series and similarly united; segments 

 of the genital pinnules very short and broad ; cirri present or absent. 



COMATULA, p. 78. 



a* elements of the IBr .series united by synarthry ; or. if by pseudo-syzygy, the 

 IIBr series are always present, 4 (3+4). 

 b' cirri present. 



