605 



Astrocnida, 301 

 Astrocrinidce, 315 

 Astrocrinus, 315 



Benniei, 315 



Astrogomphus, 301 

 Astrogonium, 296 



Astropecten aurantiacus, branchial skele- 

 ton, 351 



Astropectinidce, 296 

 Astrophytidce, 301 

 Astrophyton, 301 



Lincki, 301 



Astroporpa, 301 

 Astropyga, 290 

 Astroschema, 301 

 Astrotoma, 301 

 Atelecrinus, 313 

 Atelestocrinus, 304 

 Atlanta, 90, 109 



Peronii, 7 

 Atlantidce, 6 

 Atys, 46 



Auricula, 350, 402 



Auricularia, 506, 507, 508, 511, 512, 

 513, 514 



,, of Synapta, 512, 514 



Auriculidce, 8 

 Avicula, 17 

 Aviculidce, 17 



Axial organ ( = ovoid gland), 437, 445, 446 

 Azygobranchia, 5 



BACULITES stage, 68 

 Bcdanocrinus, 313 

 Balanoglossus, 562 



,, canadensis, 565 



Koivalevskii, 562 ; branchial 



skeleton, 580 



Kup/eri, 571 



Merschkovskii, 571 



Barrandeocrinidce, 309 

 Barrandeocrinus, 309 

 Barrel-shaped larvae (Echin.), 514 

 Barycrinus, 304 

 Basals, 318 



Basibrachial cartilage (Ceph.), 126 

 Basipterygial cartilage (Ceph.), 127 

 Basommotophora, 8 

 Bathybiaster, 296 

 Bathycrinidce, 304 

 Bathycrinus Aldrichianus, axial canals, 



378 



Bathydoris, 13 

 Batocrinus, 307 



, , pyriformis, 307 

 Baur's vesicles, 467 

 Belemnites, 24 ; shell section, 69 

 Belemnitidce, 24 

 Belemnocrinus, 304 

 Belemnoteuthis, 24 

 Seller ophontidce, 5 

 Belosepia, 24 



,, shell section, 69 



Benthaster, 298 



Benthodytes, 285 



Berghia, 13 



Bipinnaria larva, 507 ; dorsal aspect. 528 



Bivalva, 14 



Bivium, 325, 347, 407 



Blastoidea, 314 



Blauneria, 109 



Bojanus, organ of, 215, 221 



Bornellidce, 13 



Bothriocidaris, 289 



Bothriocidaroida, 289 



Botyocrinus, 304 



Bourgueticrinidce, 310 



Bourguetinicrinus, 311 



Brachiolaria larva, 508 



Branchiopneusta, 78 



Brechites (Aspergillum), 21, 20 



Brisinga, 299 



Brisingidce, 299 



Brissopsis, 293 



Brissus, 293 



Buccal shields (Oph.), 336 ; plates (Echin- 



oid.), 344 

 Buccinidce, 6 

 Buccinum, 160 

 Bidiminus, 8 

 Bulimulidce, 8, 9 

 Bulimus, 8 



,, oblongus, 75 



,, perversus, 160 

 Bulla, 10 



,, hydatis, nervous system, 140 

 Bullidce, 10 



Bulloidea (Oephalaspidce), 110 

 Bursse (Oph.), 494 

 Byssus, 112-115, 114 



CALAMOCRINUS, 310 

 Calamus, 69 

 Calcareous cells, 190 

 Calceocrinus, 304 

 Calliaster, 296 

 Callicrinus, 309 

 Callocystis, 332 

 Callum, 64 

 Calymne, 293 

 Calyptrcea, 108 

 Calyptrceidce, 6 

 Calyx, 319 

 Camerata, 306 

 Canaliculata, 310 

 Cancellariidce, 6 

 Caprinidce, 18 

 Capulidoe, 6 

 Cardiacea, 18 

 Cardiaster, 293 

 Cardiidce, 18 

 Cardita, 17 

 Carditidce, 17 

 Cardium, 18 



edule, nervous system, 144 ; tuber- 

 culatum, 18 



