ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 129 



different times in the life of the same individual. Broodiness in the 

 domestic fowl is not necessarily connected with any particular season, 

 and though it is usually preceded by the. laying of a "clutch " of eggs, 

 it is not necessarily so. Well-marked broodiness behaviour may in 

 certain cases disappear very quickly. The manifestations of the brooding 

 instinct are apparently closely connected with the functional activity of 

 the ovary, though the precise nature of the connexion has not been 

 analysed. 



Abnormal Hen's Egg.* — F. E. Chidester described a curious gourd- 

 shaped egg, which had a constricted yolk. It is regarded as probably 

 due to a constricted oviduct rather than to the fusion of two eggs during 

 apposition induced by antiperistalsis. According to Parker, doubleness 

 in eggs is due to an abnormal ovary, or to an abnormal oviduct, or to 

 both combined. Cases of ovum in ovo may be due to antiperistalsis, 

 but two ovarian follicles may combine. Fere claims that he succeeded 

 in producing double eggs in a hen which normally laid single eggs, by 

 drugging her with atropine sulphate. 



Milky-white Jell in Axolotl Spawn. f — Arthur M. Banta and 

 R. A. Gortner found a freshly-laid clump of the eggs of Ambly stoma 

 punctatum with milky-white instead of transparent jell. There was no 

 evidence of bacterial decomposition. The outer and inner egg-mem- 

 branes were transparent as usual and the imbibition of water was normal. 

 The normal jell yielded • 337 p.c. of dry material ; the white jell 

 yielded 0*361 p.c. The normal jell had an average of 8*32 p.c. of 

 nitrogen ; the white jell had an average of 9*18 p.c, in neither case 

 corrected for ash material. The difference in nitrogen-content is in the 

 same direction and of almost precisely the same amount that it would 

 be if the opaque appearance were produced by an admixture of albumen 

 with the mucin which composes the normal egg-jell. 



Accessory Appendages in Amphibian Larva. $ — A. M. Banta and 

 R. A. Gortner publish the results of some observations on' accessory 

 appendages and other abnormalities due to the action of centrifugal 

 force on Amphibian larvae. Eggs were treated in various stages from 

 unsegmented eggs to the gastrula, and the paper describes the effects of 

 the treatment on the earlier stages. At a stage when the blastopore 

 had just become evident, a centrifugal force equal to 1700 times gravity 

 killed most, but all that survived developed accessory tail-like appen- 

 dages. A force of 1350 times gravity killed very few, and the survivors 

 all showed accessory appendages. Treatment applied earlier than the 

 blastula stage, or at the advanced gastrula and later stages, produced no 

 abnormalities. There was usually only one accessory appendage to each 

 animal, though as many as four were noted. The appendages were 

 usually lateral, or even dorso-lateral in position ; they were distinctly 

 tail-like, and the myomere structure could be seen even when there were 



* Amer. Naturalist, xlix. (1915) pp. 49-51 (2 figs.). 



t Biol. Bull., xxvii. (1914) pp. 259-61 (1 fig.). 



X Proc. Soc. Exper. Biol, and Med., xi. (1914) pp. 177-8. 



