GEODIA AGASSIZII. 127 



DIMENSIONS OF MESOPROTRIAENES OF GEODIA AGASSIZII. 





2886 



2887 



2978 



3088 



3168 



4193 



4199 



4228 



4551 



From 

 all sta- 

 tions 



4228 



Rhabd- 

 ome 



length 



of apparent- 

 ly full-grown 

 spicules, mm. 







2-5 



3 5- 



5-8 



4 5- 

 5-5 





4 1-6 



6 



3.6- 

 4.3 



2-6 





average of the 

 three longest, 

 mm. 







4.7 



5 5 



5 , 1 





5 



6 



4 



5 . 1 





thick- 

 ness 



of apparent- 

 ly full-grown 

 spicules, tt 



20 



25- 

 27 



15- 

 40 



15- 

 30 



20- 

 30 



18- 

 20 



7- 

 32 



12- 

 22 



10- 

 23 



7- 

 40 



0-13 



average of the 

 three thick- 

 est, /I 



20 



27 



34 



26 



28 



19 



30 



21 



21 



25.11 



12 



Clades 



length 



of apparent- 

 ly full-grown 

 spicules, /i 



120 



150- 

 180 



125- 

 250 



60- 

 150 



150- 

 200 



90- 

 100 



100- 

 210 



90- 

 180 



90- 

 175 



60- 

 250 



95- 

 125 



average of the 

 three longest. 



120 



180 



250 



143 



178 



95 



203 



145 



142 



161 .78 



120 



angle 



of apparent- 

 ly full-grown 

 spicules, ° 



26 



35- 

 40 



SO- 

 SO 



32- 

 55 



30- 

 40 



39- 

 55 



22- 

 48 



32- 

 50 



33- 

 55 



22- 

 55 



42 



average, ° 



26 



37 



39 



39 



36 



47 



36 



41 



41 



38 



42 



Epirhabd 

 length 



of apparent- 

 ly full-grown 

 spicules, fi 



110 



110- 

 150 



70- 

 210 



60- 

 135 



25- 

 150 



60- 

 100 



90- 

 320 



78- 

 125 



60- 

 110 



25- 

 320 



35- 

 100 



average of the 

 three longest, 



r- 



110 



150 



192 



125 



136 



80 



268 



109 



93 



140 33 



95 



The anatriaenes (Plate 28, figs. 16c, 18-27; Plate 32, figs. 43, 45, 46) occur 

 in all specimens. They appear to be particularly numerous in the specimens 

 from Station 2887. The rhabdomes of the anatriaenes of the adult specimens 

 are 4-9 mm. long and at the cladome 10-50 thick, their average maximum di- 

 mensions being 6.5 mm. X 32.56 /i. The rhabdomes of the anatriaenes of the 

 specimens from Station 4199 are considerably thicker than those of the others. 

 The rhabdome is straight or slightly curved and thicker in the middle than at 



