46 Echin. 
XIY. ECH1N0DERMA. 
details of the process ; Schuecking (290). — Influence of ovum plasma, 
reply to Schuecking (290); Dungern ( 71 ). — Reply; Schuecking 
(291). 
Segmentation, — appearance of a “Gallertschicht” ; Krassuskaja & 
Landau (172). — First formation of groove studied in Strongylo- 
centrotus ; Ziegler (337) p. 170, figg. —Relation of grooves to astro- 
spheres elucidated by experimental study of mitosis in Echinus ; 
Teichmann (303). — Independence of the halves of the nucleus or 
“gonomere Zustand der Keimbahnkerne” ; Haecker (122) p. 359. — 
Abnormal mitoses in fragments of ova of Echinus microtuberculatus 
deprived of nucleus and fertilised with sperm of Strongylocentrotus 
lividus ; Boveri (22). 
y. Larval Stages : — (a) Larvae with transverse bands of cilia in Hot. , 
Crin.y Oph.y Ech., and their bearing on Echinoderm ancestry ; Grave 
( 111). (c) Normal gastrulation of Strongylocentrotus , one-tenth 
total number of cells are invaginated as in other Ech.y and not one- 
half as Boveri stated; Morgan (226) p. 122. — Movements of gastrula 
see H, c, vii; Bohn (20). — Spatangid plutei as red felt-like masses, 
G. of Trieste (p. 146), and variations of larvae in plankton (pi. i); 
Steuer (301). — Complete account of larval development of Echinus 
esculentus, and comparison with E. acutus and E. miliaris ; MacBride 
( 207) see also (210).-, —E. esculentus , 21 days, pit with nerve fibrils and 
ganglion cells; MacBride (208 & 207). — Difficulty in rearing later 
stages varies with the species, account of results with Sphaer echinus, 
Echinus , and Strongylocentrotus , also hybrids of last two ; Doncaster 
( 63). — Description of skeletons of normal and hybrid plutei of Sphaer- 
echinus and Strongylocentrotus ; Doncaster (64) p. 123 & figg. 
(d) Rearing Ast. larvae, shade, movement, and nutriment are needed j 
Delage (49). — Larvae of Luidia sarsi , young stages ; MacBride (209). 
vi. Organogeny : — (c) Echinoidea : — General account of growth and 
metamorphosis of young sea-urchin in Echinus esculentus ; MacBride 
( 207) pp. 303-310.— Abstract of Th6el (277) Zool. Rec. 1902 ; Hamann 
( 125) p. 1316. 
vii. Post-larval Growth-stages: — Growth of young Stichopus japoni- 
cus from 35 mm. to 20 mm. long, reach adult (i.e. reproductive) stage 
in 2 years, and live about 5 years (p. 11), correlation with growth of 
spicules (p. 19) ; Mitsukuri (224).— Growth of spicules in Holothuria ; 
Pearson (250) pp. 200, 204. — Ditto in Chirodota laevis ; Norman 
( 239) p. 414. (c) Development of apical area in young Phormosoma 
placenta , diam. 7-35 mm. (p. 69, pi. iv), further details in specimens 
of diam. 3-7 mm. (p. 174), brephic Hypsiechinus (p. 89, pi. vii) ; Mor- 
tensen (229). — Brephic stages of various undetermined spp. of Echinus 
from *5 mm. diam., with special reference to podia, gut, dental sacs, 
gonads; MacBride (207) pp. 310-314. — Differences between neanic 
and ephebic Iheringina\ Lambert (177) p. 478. — Neanic to ephebic 
Hemiaster cubicus ; Fourtau (88). — Differences between specimens of 
Asthenosoma varium 48 mm. & 160 nun. diameter; Doederlein (62) 
p. 703. (d) Comparison of young and adult in spp. of Cheiraster, 
Anasterias ; Ludwig (204). (f) In arms with biserial Br., the distal 
Br. originate uniserially, although they might be biserial in highly 
specialised genera, illustrated by descr. and figg. of Encrinus , Platycr ., 
Dichocr., Acrocr., Eucalyptocr . Hydreionocr., Zeacr . ; Grabau (109). 
viii. Developmental mechanics and Experimental Embry- 
ology : — General account and discussion of recent work ; Diiiesch 
( 68). — Spermatozoa of Ech., movement in a drop of water; Winslow 
( 325). — Life of ovum prolonged by sterilising sea-water; Gorham & 
Tower (107). — Experimental study of mitosis in Ech. ova; Teich- 
