40 

 Family J)( )LAT0CRINID^. 



DOLATOCKINl'H DISPAK, U. Sp. 



I'I'dIc II. Fij/. V7, side vii'ir; Fiij. 2x, hdSdl victr; I'iij. i'!K skiii 



Dill ricir. 



Spceit'S Vk'Iow nicclium size. Culyx low, .soincwhut bow;- 

 shapcf], <ii-;i(lually (>.\])an(liii.y Irom a fruiicaled basi; to the fret! 

 arms, without const riction. ivadial ridiccs sliarj)ly an.ijular aiul 

 bcai' a sliai'i) ikjiIc, at the miildlc of each ])h(t<'. ThiM'o is also 

 a shai'p node on each inlci'i'adial and a few obscure radiatin'r 

 1 lies, 'riie in'iiuaiy ladiais i)eai' no ladiatinj^ lines. Coliiinii 

 round and contains a, lai\i;'e cin(|n(' foil canal. 



Basal disc ])ent.a^onal, one fourth wider that the diameter of 

 t'le column, and contains th(> concavily into which the end of 

 tlie column is in.scM'ted. h'irst luimary I'adials nearly as lonir 

 as wide and each one b(':irs a, loniz; centi'al node, on the ]ioints 

 of which the calyx will icst. Second primary i'adials wi<ler 

 than lon<<, quadranjiular. Third primai'y radials smaller than 

 the second, pentaj?onal, axillary, and, in the ray on the right 

 of the azygous uvea, sujiport. on the distal side two secondary 

 radials and on the ju'oxiiiuil side a sinirle secondai'y radial, 

 that is axillary, and supjiorts on each ninx'r side a single ter- 

 tiary radial, and, in the ray on the left of the azygous area, 

 supports on tlie ])roxinia.l side two secondary radials and on 

 the distal side a single secondary radial that is axillary, and 

 sui)poits upon each upper side a single tertiai'y radial, which 

 gives to c;ich of these rays three arms. In ea(di lateral ray, 

 the third ]iiimary radial su])poits on each u)i]ier side a single 

 secondary radial. whi(di is axillary and supjiorls on each npiior 

 side a tei-tiary radial which arrangement gives to each of these 

 two )-ays Four aims. In the ray ()])])osite the azygoiis area the 

 third primary radial bears upon each upper side two .secondary 

 radials which gives to this ray two arms. There are, thcie- 

 fore, sixteen anus in this species. The arm formula is 3+4 + 

 -^+4+:i 



The a/.ygous ai'ea is substantially lik'i; the other areas. The 

 tiist interradials ari^ the largest plates in the calyx, liavo 

 eleven sides, and are followed by three plates in the second 

 range that unite with the plates of the \ault. 



