ZOOLOGY AND BOTANY. .MICROSCOPY, ETC. 351 



The youngest larvae to give responses to Lighi of 768 candlemeters 

 intensity were between 11 and 12 mm. Long. 



Amoeboid Movement in Melanophores of Frog.* — Davenport 

 Hooker has studied the melanophores in the corium of the larvae of Rana 

 pipiens and of the adults of R. fusca and R. pipiens. The pigment 

 granules contained within the melanophores of both larvae and adults 

 are carried in the cell cytoplasm. They are not carried in intracellular 

 canals, or along rod-like structures, or in a specialized kind of proto- 

 plasm. They show no definite relation to one another or to the nucleus. 

 In both larvae and adults the melanophores lie in preformed spaces in 

 the connective tissue and corium respectively. Those of adult frogs fill 

 the branches of their preformed spaces in the fully expanded phase, 

 those of tadpoles do not. The melanophores of adult frogs have expan- 

 sion-phase patterns which are constant for each cell and which are forced 

 upon the cells by their preformed spaces. The melanophores of both 

 larval and adult frogs expand and contract within the spaces which 

 enclose them. As the processes of expansion and contraction are 

 performed by means of pseudopodia, the melanophores are rightly called 

 amoeboid. 



Adipose Tissue, f — Ed. Retterer has studied this in the rabbit 

 and from the sole of the foot in man. Adipose tissue is preceded by a 

 reticular connective tissue, the elements of which have a granular 

 protoplasm with anastomosing meshes filled with hyaloplasm. This 

 tissue is served by a dense network of capillaries; its chromophilous 

 filaments multiply, and the hyaloplasm is transferred first into 

 adipogenous granules and then into fat globules. These accumulate 

 between the chromophilous filaments which have become partially 

 elastic. The " adipose vesicles " are not cells, but represent internuclear 

 areas charged with fat. 



L a 



Non-medullated Nerve Fibres.} — J. Nageotte finds that there is 

 complete morphological correspondence between the axis cylinder of 

 non-medullated and of medullated nerve fibres. Both contain a con- 

 siderable quantity of serous material, and differ only in dimensions. A 

 composite non-medullated fibre consists of a syncytial protoplasm 

 interpenetrated by numerous axis-cylinders, which are disposed at equal 

 distances and occupy parallel cylindrical compartments, bounded by 

 plasmic partitions. The structural units are not the axis-cylinders 

 with their plasmic surroundings, but the composite fibres themselves 

 all that is inside the syncytial sheath. 



c. General. 



Nutrition of Marine Invertebrates. § — H. Blegvad has studied in a 

 systematic way the food and conditions " of nutrition among the 

 communities of Invertebrates found on or in the sea-bottom in Danish 



* Amer. Joum. Anat., xvi. (1914) pp. 237-50 (3 figs.). 



t C.R, Soc. Biol. Paris, lxxviii. (1915) pp. 5-9. 



I C.R. Soc. Biol. Paris, lxxviii. (1915) pp. 12-16 (3 figs.). 



§ Rep. Danish Biol. Station, xxii. (1915) pp. 43-78 (4 figs.). 



