23 Echin. 
Development. 
1015 
h. Development of Pentremites 
conoideus from specimens 0‘82 mm. 
long to adults 22 mm. long, detailed 
measurements and curves, comparison 
with young Codaster ; Smith. 
8. Developmental Mechanics and 
Experimental Embryology. 
Reply to Herbst 119. Zool. Rec. 1904 ; 
Schttcking. 
Factors determining arrangement of 
chromatin and form of nucleus in oocyte, 
Antedon’, Chubb, 2, (492). 
Polarity of ovum, Paracentrotus ; 
Garbowski. 
Development of bilateral symmetry in 
Echinus microtuberculatus ; Driesch, 1 
& 2 . 
In Echinus number of primary 
mesenchyme cells conforms to that of 
mother, uninfluenced by sperm ; Peter. 
Osmosis and entrance of spermatozoa 
in Arbacia ; Ariola. 
Lack of oxygen or prevention of oxi- 
dation by KCN prevents disintegration 
of ova after membrane-formation, 
Strongylocentrotus ; Loeb, 2 & 5. 
Lack of oxygen prevents toxic effects 
of hypertonic solutions on Ecli. ova ; 
Loeb, 4. 
Chemical aspect of fertilisation; in 
Strongylocentrotus absence of free 
oxygen or addition of potassium 
cyanide check segmentation, more car- 
bon dioxide formed by fertilised ova 
than by unfertilised ; Loeb, 6. 
Effects of compression and want of 
oxygen on maturation, fertilisation, and 
segmentation of ova and sperm-ova, 
Asterias ; King. 
Sperm-ova Arbacia and Asterias 
more susceptible to cyanides just before 
and during segmentation ; Mathews, 1. 
Separation of Arbacia ovum-material 
into 4 layers by centrifugalizing ; 
fertilization ; development of sperm- 
ovum normal, except for pigmentation ; 
Lyon, 1. 
Mere shaking, without rise of tem- 
perature, does not retard segmentation 
of sperm-ova in Arbacia and Asterias ; 
Whitney. 
In segmentation, acid formation in- 
creases with number of nuclei ; Loeb, 7. 
Action of neutral salts on develop- 
ment of ova and sperm-ova, influence 
of acids and alkalies ; Loeb, 8. 
Effect of carbon dioxide on segmen- 
tation of ova and sperm-ova of Asterias ; 
Tennent & Hogue. 
Influence of temporaturo on segmen- 
tation of Strongylocentrotus sperm-ova ; 
its dependence on relation of nucleus to 
plasma ; Marcus. 
Artificial Parthenogenesis. — 
Demands free oxygen in the hyper- 
tonic sea-water, Strongylocentrotus ; 
Loeb, 3. 
Adjuvant effect of manganese, cobalt, 
nickel ; Delage, 2. 
Ova of Strongylocentrotus stimulated 
to develop by sperm of Mytilus , Chiton, 
Asterias ; Kupelwieser. 
Hybridisation. — 
Sphaerechinus granularis, Strongylo- 
centrotus lividus , Echinus microtuber- 
culatus ova and enucleated fragments of 
ova fertilised by A ntedon sperm ; Godlew- 
ski. 
Hybrid larvae in variaus combinations 
of Arbacia, Sphaerechinus, Echinus, 
Strongylocentrotus ; Fischel, 1. 
Experimental study of hybrid larvae 
of Strongylocentrotus lividus, Echinus 
microtuberculatus, and Sphaerechinus 
granularis, esp. effect of temperature 
on stereom-formation in larvae of hybrids 
and parents, comparison with results of 
Vernon, 1900, and general discussion 
of bearing on heredity ; further experi- 
ments by influencing sperm or ova, 
to discover respective effect on trans- 
mission of male and female characters ; 
Herbst, 1. 
Experiments with hybrid and partheno- 
genetie larvae of Strongylocentrotus, 
Sphaerechinus, esp. in relation to 
stereom-formation, to determine con- 
ditions of appearance of the mother- 
characters ; Herbst, 2. 
