biology, (it, b, ii, d, e; iii : C: D.) Echin. 39 
derma compared with that in Mollusca; its imperfection ; Cuknot 
( 65) p. 87. 
vi. Sensation :—Reflex and coordinated responses of the Ech. spine ; 
Uexkull (235).—Action of pedicellariae in Ech., immunity of same 
individual or spiecies ascribed to a principle— ‘ autodermin ’; Uexkull 
( 234).—Sense of smell in Synapta , otocysts as equilibrating “ po¬ 
sitional organs,'” not auditory (p. 28), coordination of tentacles and 
muscles survives cutting of nerve-ring (p. 30); Clark (57).—Ex¬ 
perimental investigation of nervous system in Echinoderma, for de¬ 
termination of coordinating centres as stages in evolution of brain ; 
Steiner (222).—Movements of various Echiuoderms ascribed to stereo- 
tropism, geotropism, and heliotropism, not to consciousness ; Loeb 
(152 a). 
vii. Miscellanea and Experimental Physiology :—Amoebocyte 
formation in parietal lacunae of respiratory trees of Holothuria and 
Stick opus ; Bordas (43).— Tonus of Holothurian muscles lost by 
warmth, increased by cold, the limits of the observation being 
6—38° C.; Schoenlein (210).—The hardening of the Holothurian 
skin in response to stimuli, and its softening into a slime under other 
conditions, especially death, chemically and microscopically examined 
in spp. of Holothuria, Stic hop us, Gucumaria, Synapta, and found to be 
due to the inhibition or excitation by the cellular elements of a 
histolytic tendency in the intercellular substance ; Lindemann (146). 
- -Temperature ( + ) at which Echinus rnicrotuberculatus, Strongylo- 
centrotus lividus, and embryos of latter are killed ; Vernon (241). — 
Pedicellariae of Asterias grasp fine threads and can support weight of 
animal; Mead (174) p. 74.—Madreporite not essential to life of 
Asterias, at least for 5 months ; Mead (174) p. 73.—Experiments on 
otocysts (see vi), ciliated funnels (see v) etc. in Synapta ; Clark (57). 
(D.) BIONOMICS. 
i. General Accounts :—Habitat, bathymetric distribution, etc. of the 
various recent Classes, from a 23akeontological point of view ; Grabau 
( 107) pp. 345-348.—Habits of larvae, young, and adult Asterias ; 
Mead (174) pp. 50, 53. 
ii. Special habits :—Social habit of Ech. and Ast. ; Se^ion (213) 
p. 505.—Phosphorescence,—in Ophiopsila anmdosa\ Lo Bianco (147) 
p. 472. See also Netting (184, 185). 
iii. Habitat:—Of Hoi., Ecli., Ast. and Oph. in English Channel; Allen 
( 8) pp. 460-476.—Of Hoi., Ech., Ast., Oph. in Lyngenfjord and 
Tromso Sound ; Bidenkap (37, 38) passim .—Of Hoi., Ech., Ast., Oph. 
and Crin. in Bay of Naples ; Lo Bianco (147), pp. 469-476.—Of 
Bermuda Hoi. ( passim ) esp. Synapta. vivipara under a stone in 
tideway (p. 125); Clark (56).—Of Synapta inlmerens, sand and mud, 
S. roseola under stones or in gravel; Clark (57) pop. 24, 25, 27.—Of 
Echinometra lucunter, which bores channels in Suva coral-reefs ; 
Agassiz (1) p. 118, pi. xxx.—Of Ast. in general; Hamann (118) p. 735. 
—Of Ophionereis reticulata, in bunches partially buried in the sand, 
and of Luidia clathrata, partly buried in sand ; Clark (56) p. 118. 
—Of Oph. at Bahamas, esp. on hard bottom and on corals; Merrill 
(244) p. 2 and passim .—Colony of Cyathidium holopus with all indi¬ 
viduals bent in same direction, probably p 0 m eet some constant 
current, orientation as yet unknown ; Hennig( 119) p. 116.—Unstalked 
Protocrinus sessile on limestone floor, cf. Marsupites and TJintacrinus ; 
Jaekel (130) p. 431.—Mode of life and habitat of Thecoidea ( = Edrio, 
asteroidea ); Jaekel (130) p. 26. 
