ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 293 



two lines of evidence confirming the individuality of the chromosomes. 

 The first of these concerns the accessory chromosome, in whose behaviour 

 he finds additional proof of its distinctness from the other chromo- 

 somes. The second line of evidence concerns the ordinary chromosomes. 

 Boveri has recently found a difference in function in the chromosomes ; 

 Sutton has found a difference in size ; and Bamngartner has been 

 fortunate enough to find a difference in form, a characteristic shape 

 assumed by the chromosomes in the prophase and metaphase of the 

 first spermatocyte division. 



Telephase in Blastomeres of Salmonidae.* — P. Bouin states that the 

 axial filaments which differentiate themselves in the course of the 

 mitoses of the large blastomeres in the Salmonidas are the following : — 

 (1) A system of fibrillar extended between the diverging kinetic centres. 

 This is the primary protoplasmic spindle ; it disappears when the 

 distance between the centres is considerable. (2) The secondary spindle, 

 a true karyodieretic spindle which is derived from the two regions of 

 the aster directed towards the nucleus. (3) A system of filbrilke 

 ■developed between the polar plates. This is the spindle residue in 

 the small blastomeres ; it is crushed by the invagination of the 

 €ell-membrane during division. (4) A fourth system of filaments 

 is constituted after the disappearance of the before mentioned set. They 

 occupy the whole equatorial region of the mother-cell, and are re-united 

 after the separation of the plasma into a sheaf-like formation. The 

 name " equatorial palisade " (palissade equatoriale) is proposed for these 

 filaments, and separation sheaf (gerbe de separation) to designate the 

 figure made by them when gathered together by the converging invagi- 

 nation of the cellular membrane. 



Morphological Superiority of the Female Sex.f — T.H.Montgomery, 

 jun., reviews a number of facts in the anatomy and development of 

 various invertebrate and vertebrate types, from which he concludes that 

 the male is the more embryonic and less developed. A survey of the 

 facts of sexual dimorphism shows the supposed excellence of the male 

 to consist in what are mainly unimportant morphological characters. 

 The female possesses an internal reproductive apparatus which is 

 generally of much greater complexity than that of the male, and some- 

 times a central nervous system of higher specialisation. Almost 

 without exception the female is larger than the male. When either of 

 the sexes is rudimentary in comparison with the other, it is in almost all 

 cases the male. The general conclusion reached is that from the stand- 

 point of morphological advancement the female is clearly the superior 

 in the invertebrates and lower vertebrates ; and still superior, but in 

 less degree, in the higher vertebrates. 



Experiments on Tadpoles.} — Empedocle Goggio has made a long 

 series of experiments on the tadpoles of the toad {Bitfo vulgaris) 

 showing the degree of viability and regenerative capacity exhibited after 



* Arch. Zool. Exp., iii. (1905) Notes et Revue, pp. xcii-c. 



t Proc. Amer. Phil. Soc, xliii. (1904) pp. 3(35-80. 



J Atti Soc. Toscana Sci. Nat, xx. (1904) pp. 1S6-223 (2 pis.). 



