RECENT ADVANCES IN SCIENCE 235 



Its ventro-lateral portion is a derivative of the second myo- 

 tome, and its dorsal-median part comes from the third myotome, 

 a conclusion previously put forward by Bohrn in 1904. 



Other papers include : " Metabolic Activity of the Ner- 

 vous System, ii. The Partition of Non-Protein Nitrogen in 

 the Brain of the Grey Snapper (Neomcenis griseus), and also 

 the Brain Weight in Relation to the Body Length of this 

 Fish," by Hatai (Journ. Comp. Neur. vol. xxix. February 191 8) ; 

 " A Seasonal Study of the Five-spined Stickleback," by Hess 

 (Anat. Rec. vol. xiv. February 191 8) ; "A Bibliography of 

 Fishes," vol. ii. Authors' Titles L-Z, by Dean, enlarged and 

 edited by Eastman (Amer. Mus. Nat. Hist. 191 7); "The 

 Results of Thyroid Removal in the Larvae of Rana pipiens," 

 by Allen {Journ. Exp. Zool. vol. xxiv. January 191 8); 

 " Some Experiments on Regeneration after Ex- Articulation in 

 Diemyctylus viridescens," by Morrill (ibid. February) ; " The 

 Effect of the Extirpation of the Thyroid upon the Thymus and 

 the Pituitary Glands of Rana pipiens," by Rogers (ibid. 

 January) ; " The Effects of Inanition upon the Development 

 of the Germ Glands and the Germ Cells of Frog Larvae," and 

 " The Acceleration of Metamorphosis in Frog Larvae by 

 Thyroid Feeding and the Effects upon the Alimentary Tract 

 and Sex Glands," both by Swingle (ibid.) ; " Effects of the 

 Extirpation of the Thyroid Gland in Rana pipiens," by Terry 

 (ibid.) ; " Studies on the Growth of Blood-vessels in the Tail 

 of the Frog Larva — by Observation and Experiment on the 

 Living Animal," by Clark (Am. Journ. Anat. vol. xxiii. January 

 1 91 8); and "Pharyngeal Derivatives of Ambly stoma," by 

 Baldwin (Journ. Morph. vol. xxx. March 191 8). 



" The Formation and Structure of the Zona Pellucida in 

 the Ovarian Eggs of Turtles," by Thing (Am. Journ. Anat. vol. 

 xxiii. March 191 8) includes an account of a structure whereby 

 nutritive material can be conveyed from the maternal blood 

 to the forming yolk. It is composed of a number of very fine 

 filaments from the surrounding epithelial cells which penetrate 

 the homogeneous substance of the zona and end in knob- 

 like swellings on the yolk. The somewhat complex formation 

 of the zona itself is also fully dealt with. 



Other papers include : " Concerning the Renal Portal 

 System in Chrysomys marginata," by Robinson (Anat. Rec. 

 vol. xiv. January 191 8). 



