GEODIA AGASSIZII. 241 



Northeastern Pacific. West coast of North America; 33° 38' 45" N. 

 "Albatross" Station 2942. 



Geodia agassizii Lendknfeld. 

 Ante, p. 113. 

 Cydonium midleri Lambe (non Fleming), Trans. Roy. soc. Can.ida, 1S9.3, 11, p. .36, plate 4, fig. 2. 



The following description is also based on an examination of the tj'pe speci- 

 men of Cydonium midleri Lambe 1893, in the collection of the Geological Survej'' 

 of Canada. 



Massive, spherical, oval, elongate or somewhat irregular; without praeos- 

 cular cavities. In spirit: uniformly white to light brown, some with dark brown 

 patches, some dark blue. 



Large amphioxes: of adult 2.3-4.8 mm. by 60-112 /«; of immature 1.8- 

 3.4 by 20-66 p.. Large amphistrongyles: only in the immature, a little shorter 

 than the amphioxes, 55 /< thick. Large, slender styles: rather rare, not in all 

 specimens; of adult 1.5-3.4 irnn. by 60-110 p.. Large, stout styles: rare, only 

 in some specimens; of adult at thickened rounded end 115-145 /i thick. Minute 

 dermal amphioxes: of adult 160-480 by 5-12 /x; of inmiature 180-480 by 3-8 p. 

 Orthoplagiotriaenes of adult: rhabdome 1.5-4.3 mm. by 65-150 /«; clades 240- 

 560 n long, simple, more rarely with irregular branchlets; clade-angles 73-117°; 

 of immature: rhabdome 2 3.5 mm. by 50-100 /«; clades 300-500 /« long; clade- 

 angles 88-108°. Regular dichotriaenes: only in the smallest immature specimen, 

 rhabdome 1-2.2 mm. by 50-75 p.; main clades 150-300, end clades 30-130 p 

 long; angles of main clades 109-112°; cladome 350-700 p broad. Mesortho- 

 triaenes: rare, not in all specimens; in the adult, a style-like shaft 1.8-3 mm. 

 by 78-164 p at the rounded end, with clades 78-300 p long, inserted near the 

 rounded end and concave towards it. Irregular amphiclade orthoplagiotnaene, 

 dei-ivates: rare, not in all specimens, dimensions as in the orthoplagiotriaenes, 

 but with a branch-ray on the rhabdome, besides the ordinary clades. Mesopro- 

 triaenes of adult: rhabdome 2-6 mm. by 7-40 p; clades 60-250 p, epirhabd 

 25-320 p long; clade-epirhabd angles 22-55°; of inimature: rhabdome 9-20 p. 

 thick; clades 60-125 p, epirhabd 70-100 p long; clade-epirhabd angles 36-47° 

 Large anatriaenes of adult: rhabdome 4-9 mm. by 10-50 p; clades 40-155 p 

 long, clade-angles 32-65°; of immature: rhabdome 3.3-4.7 mm. by 18-28 p; 

 clades 45-110 p long, clade-angles 31-52°. Irregular anatriaene-derivates: 

 rare, not in all specimens; dimensions as in the regular anatriaenes. Minute 

 dermal anaclades: rare, observed only in the smallest immature specimen; 



