EMBRYOLOGICAL. 
Gen. Sub '. 51 
layers, coelome, &c., in Amphioxus ; MacBrjde (428). — The coelom 
theory; Castle (105). — The Urmimd- theory and its application to 
Amniota ; Will (715). — Norm-tables of Vertebrate development ; 
Keibel (357). — Conditions of development in Echinoderms ; Driesch 
(172). — “ Critical stage ” in the development of Scyllium and Lepidosteus , 
when the embryo definitely makes for the adult form, suppressing its 
larval foundation ; Beard (54). — Protoplasmic connections between 
blastomeres ; Hammar (305). — Development of pig ; a very important 
paper ; Keibel (358). — History of a transient nervous apparatus in the 
skate ; Beard (49, 52). 
External conditions of development in Sana temporaria ; Samapsa 
(599). — Stimuli in development ; Roux (584). — Has the central nervous 
system an influence on the processes of larval metamorphosis ? Cutting 
the spinal cord seems to make little difference. Morphogenetic functions 
are less dependent on the central nervous system than are motor and 
sensory functions ; Loeb (420). — A contribution to developmental 
mechanics, re Asplanchna herriclm ; Jennings (351). — The course of 
cleavage in Asplanchna is inconsistent with any general validity of 
(1) Hertwig’s hvw of the spindles in the longest axis of the protoplasmic 
mass, (2) Berthold’s law of least areas, and (3) Braem’s & Pfluger’s 
principle of least resistance ; Jennings (351). — Developmental mechanics. 
The early development of Asplanchna, to a stage somewhat beyond 
gastrulation, may be analysed into two factors : (1) the influences deter- 
mining and preserving the form of the egg as a whole, and (2) processes 
■occurring in consequence of the specific (molecular) structure and activi- 
ties of the protoplasm; Jennings (351). — Ontogenic recapitulation of 
phylogenetic coloration ; Ureci-i (673). — Recapitulation ; Beard (54), 
Sedgwick (626). 
The meaning of metamorphosis ; Hyatt & Arms (346). 
b. Particular Organs and Parts. 
Development of musculature ; embryonic and larval variations can 
alone explain the’ differences in the adults ; Nussbaum (502). — 
Differentiations of the ectoderm ; development of peripheral nervous 
system in Necturus ; Platt (542). — Ectoderm in bud bf Perophora, 
cinnectens is differentiated from the first, thus the endoderm has to 
form nervous system, &c. Contrast the jellyfish, Rathlcea octopunctata , 
where the endoderm takes no part in the formation of the bud ; 
Ritter (572). — Disappearance of the transient nervous system in 
Elasmobranchs ; suggested explanation of the different degrees of 
disappearance ; Beard (52). — Yolk and yolk-sac in Scyllium and 
Lepidosteus. The yolk of Scyllium- ovum, after preparation by 
merocytes, is first absorbed by the blood-vessels of the yolk-sac ; but at 
the critical period an internal j^olk-sac is formed, whence the yolk passes 
into the gut, and is digested. The merocytes remain in and degenerate 
in the degenerating yolk-sac. In Lepidosteus , however, they gorge 
themselves with yolk, and pass into the embryonic gut by a passage or 
yolk-bay formed at the critical period ; Beard (51). 
Merocytes and the blastoderm-margin in Teleostei ; Corning (131). — 
Origin of periblast in Teleostei ; Ziegler (736). — Parablast and germinal 
layers in Teleosteans ; Berent (59). — Development of Ascaris megalo- 
cephala. Study of cell-lineage, chromatin-diminution, &c. ; Zoja (739). 
Cell-lineage, &c., in development of Limax maximus ; Meiseniieimer 
(453). — Origin and import of the foetal membrane of Vertebrates ; 
Semon (631). — Development of pancreas and liver in Selachians, 
Reptiles, and Mammals ; Braciiet (81). — Development of liver and 
