602 



INDEX 



circular apical perforation in, 



389. 

 discussion of, 356. 

 sinus and fold in, 388. 

 variation in, 66. 

 variations in stock of, "Wil- 

 liams, 25. 

 volutions in spiral cone of 

 mature, 417. 

 rugosa, 357. 

 spinosa, 25. 



spines in, 51. 

 tumida, Sll. 



whorls in spirals of, 416. 

 young condition in, 417. 

 Atrypidffi, 283, 416. 



brachial supports in, 276. 

 converging cones in, 283. 

 origin of, 417. 

 whorls in spirals of, 416. 

 Atrypina disparilis, 315, 364. 



discussion of, 369. 

 Aitheya decora, spine growth from 

 frustule of, 43. 

 spines from angles of, 44. 

 Aulocrinus Afjassizi, spines on terminal 



sacs of, 45. 

 Aulopora, 425, 427. 

 corallites in, 427. 

 subtenuis, 427. 

 visceral cavities in, 425. 

 Aulosteges, 69, 70, 96, 245, 270. 



spines on deltidium of, 260. 

 Avalonia, 140. 



glabella in, 141. 

 Avicula, 255. 



dissoconch growth in, 23. 

 smooth prodissoconch of, 18. 

 sterna, nepionic stages of, 20. 

 prodi-ssoconch of, 20. 

 spines in, 51. 

 Aviculid.-B and allied forms, Lower Si- 

 lurian nuculoid radicle for, 23. 

 Aviculopecten, 23. 



ornatus, spines in, 51. 

 scabridus, spines in, 51. 



B 



Bactrynium, 245. 



Baculites a typical phylogerontic form, 

 Hyatt, 91. 



Bailey, L. H., culmination and descent 

 of Echinodermata, 26. 

 spinous processes on the plant body, 

 90. 

 BailieJla, 140. 

 Bailey i, 178. 

 glabella in, 141. 

 Balanophorea;, spiniform scales in, 83. 

 Balanus, 188. 



tintinnabidiim, var. spinosus, spines 

 on, 52. 

 Balfour, F. M., defensive spines in nau- 

 plius larva of Lcpas fascicxdaris, 

 56. 



development of Apus, 189. 

 variation in uauplius of trilobites, 

 191. 

 barberry, disappearance of spines on, 

 Lothelier, 74. 



indirect growth of spines in, 12, 13, 



14. 

 leaves of, transformed into spines, 



75. 

 thorns of, 10. 

 barnacles, spines on shells of, Darwin, 



52. 

 Barrande, J., classification of trilobites, 

 110, 132. 

 description of elementary forms of 



trilobites, 176. 

 determination of sutures in Trinu- 



cleus, Dionide, and Harpes, 134. 

 development of trilobites, 310. 

 generic names for Agnostus, 136. 

 metamorphoses of trilobites, 166. 

 orders of development in trilobites, 



167. 

 possible trilobite eggs, 169. 

 Sao hirsnta, 166. 

 Barrandia, 146. 

 Basilicus, 146. 



Batcson, W., horns in some Hercules 

 beetles, 59. 

 repetition of parts universal among 

 organisms, 67. 

 bathmic energy, 34. 

 force. Cope, 29. 

 Bathynotus, 140. 



glabella in, 141. 

 Bathyurellus, 146. 

 Balhyuriscus, 146. 

 Bathyurus, 146. 



