ZOiJLOGV AND liOTANV, MIGKOSCOPY, KIC. 473 



served as soon as possible after the ouset of heat there is likely to be 

 discerned in a period of years, a reduction in the number of male calves 

 born. 'It may be that the general metabolic condition of the germ-cells 

 influences the rf^-chromatin. 



b. Histology. 



Combinations of Chromatophores.* — E. Ballowitz has previously 

 directed attention to multicellular combinations of iridocytes and melano- 

 phores. He now describes in the skin of Gobies two kinds of chromato- 

 phore combinations. There are black-red coml)inations — melanophores 

 and erythrophores. Sometimes these are double cells ; sometimes 

 several or even numerous young erythrophores form clumps along with 

 a melanophore, or with several melanophores. The melanophore por- 

 tion is usually round about the erythrophore portion. 



In the second place there are stellate associations — of narrow elon- 

 gated thin iridocytes, usually with a nucleus. They form a rosette or 

 star, and there may be from two to twenty-five. With these rosettes 

 there may be associated chromatophores, e.g. about five melanophores 

 on the dorsal surface of one iridocyte-star, or a central melanophore, or 

 a black-red combination forming half of the star. The chromatophore 

 cytoplasm is traversed by very numerous extremely fine canaliculi, 

 radially disposed and anastomosing with one another. In these cana- 

 liculi the streaming of the pigment is to be seen, continuing for hours 

 in the living tissue under the Microscope. 



Minute Structure of Hairs. f — Karl Toldt, jun., discusses in the 

 first place the distribution of the main hairs (" Leithaare ") which are 

 relatively long and strong. He has studied numerous types of Mammals 

 and finds that the distribution of the main hairs is not related to the 

 mode of life. 



The embryonic and subsequent development of the cat's fur is then 

 dealt with. The rows of epidermic thickenings, which are to be regarded 

 as the predecessors of hairs, and the arrangement of hair-primordia in 

 the embryo, can be correlated with the subsequent marking. 



Hairs often show external furrows parallel with the long axis and 

 sometimes spirally twisted. These may facilitate the running off of 

 water or of particles. There are also internal ridges which bind cortical 

 and medullary substance together, strengthening the hair without loss 

 of elasticity. The author also discusses the linear pigmentation of some 

 hairs, e.g. of Antilocapra americana ; the remarkably complicated mark- 

 ing of the cuticula of the bristle-spines in Platacanthoniys lasiurus (per- 

 haps increasing slipperiness), and an interesting fungus in the cortex of 

 the bristles of Zaglossus {Proechidna) bruijni. 



Minute Structure of Lamprey's Ear. J — F. K. Studnicka describes 

 the state of the ear in the young larva of Petromyzon, and in later stages. 

 In the larva of 10-13 mm. it is a very primitive organ, with a large 

 otolith and two otoconial layers lying at right angles to one another. It 



* Anat. Anzeig., xliv. (1913) pp. 81-91 (29 figs.), 

 t Zool. Jahrb., xxxiii. (1912) pp. 9-86 (2 pis.). 

 X Anat. Anzeig., xlii. (1912) pp. 529-62 (17 figs.). 



