34 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



in Asteromelra, but closer to the periphery of the ossicle. The fifteenth brachial has 

 19 septa, about 9 complete. The twenty-third brachial (third hypozygal) has 18 

 septa, of which 7 are complete. 



ASTEROMETRIDAE 



Asterometra anthus.- In a specimen with arms 80 mm. long the third brachial 

 has 29 septa, of which 14 are complete; in some cases the septa are forked; the areola 

 is narrow; the degree of strength is 3. There is a concentric furrow about midway 

 between the periphery of the joint face and the central lumen. In another case 

 there are 27 septa. The ninth brachial (second hypozygal) has 28 septa. 



THALASSOMETRIDAE 



Stylometra spini/era.- In a specimen with arms about 90 mm. long the third 

 brachial, following a IIBr axillary, has 23 septa, of which 9 are complete and 2 are 

 indistinctly separated ventral beans; a couple of septa are forked, and some of the 

 ventral ones are partly subdivided into rows of tubercles; the areola is broad and 

 stout; the degree of strength is 3-4. Two third brachials following a IIIBr axillary 

 have 19 and 20 septa, with the ventral beam not subdivided; the areola is as before, 

 but the septa are somewhat lower. 



Oceanometra annandalei. In a specimen with arms 80 mm. long the IIBr 3 has 

 about 18 septa. The third brachial has 19 septa, including 6 complete septa and one 

 ventral beam; the areola is broad, though rather low; the degree of strength is 2-3. 

 The septa are stout, running out as ribs to the margin of the ossicle, and there is a 

 marginal growth ledge. 



Stenometra dentata. In a specimen with an arm length of about 50 mm. the 

 third brachial has 18 septa, 8 of which are complete and 2 are low ventral beams; the 

 areola is rather narrow and indistinct; the degree of strength is 2-3. 



CHARITOMETRIDAE 



Perissometra cf. aranea.' In a specimen with arms about 80 mm. long the third 

 brachial has 22 septa, 4 complete and 2 ventral beams; the areola is indistinct; the 

 degree of strength is 2. The thirteenth brachial has 20 septa, 10 complete and 2 

 ventral beams. The eighteenth brachial has 19 septa and a narrow areola. The 

 twenty-third brachial has 17 septa. The twenty-ninth brachial has 17 septa, of 

 which 2 are complete. The thirty-fourth brachial (sixth hypozygal) has 14 septa, all 

 incomplete, and no areola. 



Crossometra septentrionalis.- -A specimen with an arm length of 70 mm. has the 

 IIBr 3 with 17 very low septa, about 7 incomplete, with the degree of strength 1. 

 Three first brachials have 14, 14, and 16 septa. A third brachial has 16 septa, 4 

 complete and 2 ventral beams; the areola is of medium width, but low. The eleventh 

 brachial has 15 septa, 3 complete and 2 ventral beams, with the degree of strength 2. 

 In one case the articulation between the first two brachials is a compromise between 

 a synarthry and a syzygy. 



Diodontometra bocki.' In a specimen with the arms 60 mm. long the third brachial 

 has 16 septa, 6-7 complete and the ventral beam weakly developed and partly divided; 

 the degree of strength is 1 ; the areola is distinct. 



