38 
SUMMARY OF CURRENT RESEARCHES RELATING TO 1 
draw together till there may be 14-16 layers of them. The outer layers 
become horny and are cast ; the cells of the lower layers break up, their 
cell-substance becoming vesicular and rich in granules and pigment. 
Eberth’s bodies swell up and disappear. The leucocytes were not seen 
to share in the disruption of the skin. 
The muscles. Special “sarcolytes ” arise from amitotic proliferation 
of the sarcoplasm, and in these, which Metschnikoff called “ muscular 
phagocytes,” intracellular digestion of debris occurs. But much of the 
debris is simply dissolved away in the fluids of the body. 
The notochord becomes folded in numerous loops, the clastica swells 
up and dissolves, the internal sheath shows abundant amitotic divisions. 
The notochord begins to break up, numerous refractive granules make 
their appearance, cells from the skeletogenous layer enter the debris and 
probably help in disruption. Nothing decisively pointing to the im- 
portance of leucocytes was observed. 
Noetzel goes on to describe the degeneration of the caudal nervous 
system, which he seeks to bring into line with pathological processes, 
and he finishes up with the blood-vessels and blood. But the most im- 
portant result is the general one, that the importance of leucocytes in 
this connection has been exaggerated. They are not markedly abun- 
dant, they seem to do little more than take up pigment-granules or other 
insoluble particles. All the material which becomes fluid passes directly 
into the juices of the body. 
Gastrulation in Axolotl and Frog.* — Herr F. Kopscli has studied 
this photographically. Four stages are distinguishable — the incipient 
invagination, the U-shaped blastopore, the circular blastopore, the 
closure of the blastopore and the formation of the anus. The position 
of the first invagination in the brown frog is 20°— 30° below the equator, 
somewhat deeper in the axolotl. The movement of the dorsal blas- 
topore lip is real, not apparent, and occurs over about 75°. Boux’s con- 
clusion as to the congruence of the first cleavage plane and the median 
plane of the embryo is mistaken. In neither frog nor axolotl is there 
concrescence in the sense in which His uses this term. 
Superficial Epidermic Envelope in the Developing Ova of Tele- 
osteans.f — Dr. F. Baffaele describes this layer — known as Dechschicht , 
lame enveloppante, &c. — which is precociously differentiated from the 
blastoderm in bony fishes. The ova studied were apparently those of a 
species of Exocoetus. 
The epidermis, both embryonic and extra-embryonic or vitelline, 
exhibits two layers, which are minutely described. The superficial 
epidermic stratum is differentiated precociously by a modification of the 
superficial cells of the blastoderm. It grows partly by superficial in- 
crease of individual cells and partly by cell-division. The author was 
surprised to observe rapid contractions apparently in the superficial 
epidermic cells, but. he was unable to determine whether the deeper 
epidermic layer and the mesoblast cells were or were not also involved. 
In the nuclei of the superficial epidermic layer phenomena indicative of 
degeneration were observed. Baffaele also describes the division of the 
* Verh. Anat. Ges., ix. (1895) in Anat. Anzeig. Erganzungsheft, x. (1895) 
pp. 181-9 (4 figs.). f MT. Zool. Stat. Neapel, xii. (1895) pp. 169-207 (1 pi.). 
