BIOLOGY. (II, A: B, i, a.) 
EcJtin . 33 
II. BIOLOGY. 
(A.) EVOLUTION. 
i. General Principles :—Regularity of structure repeatedly induced 
by sessile mode of life, exemplified by Ecliinoderma; Steinmann (223) 
p. 25. See also Jackson under ii, f, i. 
ii. Relations of Echinoderma :—to lower Chordata , Enteropneusta , 
etc.; grouped with Ilemichorda as Bilateralia , which is not intended 
as a taxonomic division, also characterised as Hydrotrema as opposed 
to Branchiotrema ,; Willey (255) pp. 296, 297.—Relations to a supposed 
primitive group, Archicoelomata , and to the hypothetical ancestor of 
that group; Masterman (169).—Relations of larvae to Protochordata ; 
Masterman (168).—Phylogeny of Animal Kingdom; Andres (13). 
Origin of Echinoderms, “Stem cloven into two” [i.e. Pelmatozoa 
and Eleutherozoa\ “at the very base 5 ’; MacBride (165).—Light 
thrown by palasontology on the Pentactaea theory; Steinmann (223) 
p. 23. 
iii. Phytogenies of smaller groups General interrelations of 
Classes of Echinoderma ; Bather (22) p. 917. 
Change of form in Elpidiince; Herouard (121), p. 172, text-fig. 4. 
Evolution of Echinoidea from Asteroidea maintained, origin of 
buccal armature; Sollas (216) p. 710.—Evolution of Cretaceous 
species of Micraster , from zone of Rhynchonella cuvieri to that of 
M. coranguinum ; Rowe (202).—Evolutionary change of miliary 
granules and tubercles in Micraster cor-anguinum group during 
Senonian time; Lambert in Fortin (89) p. 360.—Supposed genetic 
relations of Tertiary Ecli. in northern California; Merriam (175) 
p. 165.—Evolution of Pliolampas and Botliriolampas from Echinanthus 
and Bothriopygus respectively ; Gauthier in Fourtau (96) p. 654. 
Evolution of Ast .; Hamann (118) pp. 740-743. 
Evolution of Pelmatozoa and relations to other Echinoderma , recog¬ 
nition as a Sub-phylum (p. 917), Phylogeny of Crinoidea (p. 918); 
Bather (22).—Relations of Crinoidea to Cystidea , in light of Stropho- 
crinus , dual origin of Monocyclica ; Sardeson (207) pp. 269 et sqq. 
Evolution and phylogeny of Cystidea; Bather (22) p. 917.— 
Relations of Cystidea (Jkl.) to other Echinoderms, and their own 
phylogeny (pp. 155-174), Phylogeny of Scoliocystidce (p. 247), Phylo¬ 
geny and relations of Caryocrinidce (p. 305), Phylogeny of Echino- 
sphaeridce (p. 324), Phylogeny of Diploporita (p. 368), Phylogeny of 
Thecoidea { — Edrioasteroidea) (p. 29); Jaekel (130). 
Blastoidecc, origin, relations, and principles of classification ; 
Bather (22) pp. 917, 918. 
(B.) MORPHOLOGY. 
i. Anatomy:— 
a. ECHINODERMA. 
1. General accounts:—Vacant. 
2. Symmetries :—Origin of radiate and esp. pentamerous sym¬ 
metry; Bather (22) p. 917. 
3. Homologies of Classes :—Vacant. 
J. Skeletal tissue or Stereom :—Vacant; but see (c, f, g) J. 
5. Skeletal Anatomy :—A'acant. 
6. Hydrocoel &c.:—In evolution of nephridia, definite regional 
pores suggested as differentiation from “ indefinite condition as 
