242 



GEODIA MESOTRIAENELLA. 



rhabdome 290 /< by 1-1.5 [i at the cladome and 3-5 /x at its thickest point below 

 the middle; clades 4-6 /£ long ; clade-angles 38-62°; possibly foreign. 



Large oxyasters of adult: from four to sixteen rays, 0.8-3.2 /i thick, distally 

 spined, pointed to truncate; centrum small; total diameter 9-31 /x; of immature: 

 from seven to fourteen rays 0.8-2.3 /j. thick; centrum small; total diameter 13- 

 25 ft. Large oxysphaerasters oi adult: in some specimens rare; from fourteen to 

 twenty-eight or more conical, pointed or blunt, distally spined rays, 1-2 //thick; 

 centrum 3.5-11 ji, whole aster 10-21 fi, in diameter; of immature: from ten to 

 thirty rays, 0.9-2 /i thick; centrum 2.7-7 /x, whole aster 8-21 //, in diameter. 

 Small strongylosphaerasters of adult: six to twenty rays, 0.6-1.6 pt thick; centrum 

 1.5-6 n, whole aster 3.5-11 n in diameter; of immature: from ten to twenty-eight 

 rays, 0.5-1 /i thick ; centmm 2-3.5 fi, whole aster 5-9 fi, in diameter. Sterrasters 

 of adult: 82-118 by 75-100 by 58-83 /x; of immature: 76-110 by 70-92 by 60- 

 75 /X. Sterroids: rare; similar to, but mostly somewhat smaller than, the sterr- 

 asters, and with thicker rays; their strongylaster-like young stages only in 

 the immature specimens. 



Northeastern Pacific. West coast of North America ; from 33° 59' 45" N. 

 to the vicinity of Naha Bay, Behm Canal, S. E. Alaska. "Albatross" Stations 

 2886, 2887, 2978, 3088, 3168, 4193, 4199, 4228, 4551 : Queen Charlotte Island, 

 Houston Stewart Channel. 



Geodia mesotriaenella Lendenfeld. 

 Ante, p. 151. 



Nearly spherical. Inspirit: dirty white. 



Large amphioxes: 2-2.6 mm. by 20-50 /x. Minute dermal rhabds: mostly 

 styles; 196-260 by 4-5 fi. Orthotriaenes: rhabdome 2.1-2 A mm. by 75-120 [i; 

 clades concave to the rhabdome, 350-600 /(long; mostly simple, rarely bifurcate; 

 clade-angles 90-96°. Mesoprotriaenes: rhabdome 2.8-3.4 mm. by 9-19 at 

 the cladome, thicker in the middle; clades 100-220 p. long; clade-angles 30- 

 47°; epirhabd 70-165 /i long. Anatriaenes: rhabdome 3.7 mm. by 18-30 /r, 

 clades usually simple, rarely bifurcate, 87-140 /t long; clade-angles 41-47°. 



Large oxyasters: from five to eleven conical, blunt, distally spined rays, 1.5- 

 2.8 /« thick; centrum small; total diameter usually 17-26 //, rarely up to 40 p, 

 these large asters perhaps foreign. Large oxysphaerasters: from fifteen to 

 twenty-three conical, pointed rays with a few spines, 2-2.5 {x thick; centrum 6- 

 9 /I, whole aster 20-21 /i, in diameter. Small strongylosphaerasters: from three to 

 twenty-five, usually from ten to seventeen rays, 0.5-1 n thick; centrum 1.6-4.5 /t, 



