304 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



and on the interradial processes the centrodorsal has a few small tubercles or teeth 

 which become somewhat larger and more numerous on the bare dorsal pole. The 

 smaller tubercles run outward as far as the second or third brachials. On the first three 

 brachials beyond these there is one, or on syzygial pairs two, median tubercles or humps, 

 this variety in this respect quite resembling var. pulchella and var. concinna. The five 

 specimens of var. tuberosa also agree essentially with these varieties in the ornamenta- 

 tion of the brachials following, from the third to about the sixth, eighth, or tenth. 



In the specimen from Blake station 198 the tubercle in the middle of the brachials 

 is not so large as it is in var. pulchella and in var. concinna; this specimen also has more 

 rectangular lower brachials than the others in which diagonal articulations occur after 

 the third brachial. All five specimens first show typical triangular brachials after about 

 the tenth. On many arms at the same time or somewhat earlier or later, the more or 

 less crenulate and everted distal ends appear in typical liplike form. These liplike 

 eversions appear prominently as in var. pulchella and in var. concinna only on a few of 

 the following brachials on from four to eight then gradually become smaller, dis- 

 appearing slightly beyond the elevated tubercles on the dorsal surface of the brachials. 

 Toward the arm tips the triangular form of the brachials passes over into a bluntly 

 wedge-shaped form. 



Hartlaub described all the specimens of this variety in detail. He noted that the 

 three from an unknown locality agree so completely that they may be described to- 

 gether. 



The centrodorsal is rather flat, subhemispherical. The very small free dorsal pole 

 is not sharply differentiated. Prominent interradial processes are present, reaching to 

 the height of the IBri, but no interradial ridges. The cirri are arranged two or three 

 in a vertical column. 



The cirri are XX-XXV, 14-16; the first three segments are short, and the ante- 

 penultimate has a conspicuous opposing spine. 



The radials are concealed. The IB^ are short and are thickly covered with coarse 

 tubercles. The IBr 2 (axillaries), like the IIBr axillaries, are rhombic. All the IIBr 

 series are 2, and a single IIIBr series is 2. 



Arms arising from a IBr axillary are rare. The arms hi the three specimens num- 

 ber 17, 19, and 21. So far as may be determined by external observation, the first two 

 brachials are always united by muscular articulation. The first syzygy is almost with- 

 out exception between brachials 3+4, the second from between brachials 9+10 to 

 between brachials 21+22, often between brachials 14+15, 15 + 16, or 17 + 18. The 

 third syzygy follows at intervals of from 5 to 18, often 7, 8, 9, and 11 muscular articu- 

 lations, and the distal intersyzygial interval is 3-12 muscular articulations in one 

 specimen 4-12, usually 7 or 8; in another 5-9, usually 6-8; and in the third 3-11, 

 usually 6 or 7. 



PI is about 9 mm. long with 25-30 segments of which usually the first four are 

 strikingly broad and narrowly carinate on both sides; the fifth and sixth segments are 

 moderately broad and are usually somewhat keeled on one side. The shape of these 

 proximal segments, or indeed that of the whole pinnule, does not entirely agree with 

 that of var. insculpta; there are, to be sure, marked variation hi comparable pinnules 

 of one and the same specimen. The segments following are rectangular or rounded; 

 elongate segments are lacking. Because of the strong expansion of the four proximal 



