26 BULLETIN 84, UNITED STATES NATIONAL MUSEUM. 



The succeeding plates progressively assume the shape of a triangle, and then of a 

 lozenge, and they become much smaller. The characters of the under face of the 

 disk and of the arms rather recall those indicated by Verrill, though vdth the 

 mouth shields somewhat shorter; the brachial spines, which always number two, 

 are identical. 



Owing to these variations, I do not think it useful to maintain the variety 

 elegans established by Verrill, which is based only upon the number of the brachial 

 spines, which are three in number. 



The type of 0. ebumeum described by Lyman came from the coast of Florida, 

 from a depth of 325 fathoms. The Blal-e found the species in the Gulf of Mexico and 

 in the Caribbean Sea, in depths ranging from 92 to 400 fathoms. Verrill's speci- 

 mens came from off Havana, between 110 and 260 fathoms. 



OPHIOMUSItrM LYMANI Wyville Thomson. 



See for bibliography: 

 Koehler (09), p. 161. 



Alhatross station 2102. Nov. 5, 1883. Lat. 38° 44' N.; long. 72° 38' W.; 

 1,209 fathoms; glob, oz.; temp. 39° F. Twenty-three specimens. 



Albatross station 2111. Nov. 9, 1883. Lat. 35° 09' 50" N.; long. 74° 57' 

 40" W.; 9.38 fathoms; gn. m. Eleven specimens. 



Albaiross station 2115. Nov. 11, 1883. Lat. 35° 49' 30" N.; long. 74° 34' 

 45" W.; 843 fathoms; m. fne. s.; temp. 39° F. Fifteen specimens. 



Albatross station 2678. May 6, 1886. Lat. 32° 40' N.; long. 76° 40' 30" W.; 

 731 fathoms; It. gy. oz.; temp. 38.7° F. Many specimens. 



Albatross station 2751. Nov. 28, 1887. Lat. 16° 54' N.; long. 63° 12' W.; 

 687 fathoms; bu. glob, oz.; temp. 40° F. Many specimens. 



OPmOMUSIUM PLANUM Lyman. 



See for bibliography: 

 Koehler (09), p. 162. 



Albatross station 2097. Oct. 1, 1883. Lat. 37° 56' 20" N.; long. 70° 57' 

 30" W.; 1,917 fathoms; glob. oz. Eleven specimens. 



Albatross station 2098. Oct. 1, 1883. Lat. 37° 40' 30" N.; long. 70° 37' 

 30" W.; 2,221 fathoms; glob. oz. Two specimens. 



The diameter of the disk ranges between 15 and 22 mm., in a specimen from 

 station 2097 it is only 7 mm. 



In the larger specimens, the internal tentacular scale of the first brachial pore 

 is sometimes divided in two as I have pointed out in some samples gathered by the 

 Princesse Alice in the Eastern Atlantic (09, p. 162); the brachial spines always 

 remain little developed and vary somewhat as to their number. 



OPmOMUSrUM RUGOSUM, new spetles. 



Plate 1, figs. 7-8. 

 Albatross station 2342. January 19, 1885. Lat. 23° 10' 39" N.; long. 82° 20' 

 21" W.; 201 fathoms; co. Two specimens. 

 Type.—C&i. No. 16378, U.S.N.M. 



