40G SUMMARY OF CURRENT RESEARCHES RELATING TO 



fresh-waters of America there is much more provision made for the care 

 of the young than in the cooler waters of the northern continent. 



Sub-Species of Mustelidae.* — G. E. H. Barrett-Hamilton describes a 

 number of examples of various species so differentiated as to merit rank- 

 ing as sub-species. In the pine-marten he finds a tendency to deeper 

 coloration, and a brighter throat-patch in the southern representatives of 

 the species. Among the polecats in the south the tendency is to assume 

 yellow under-fur and face markings, while in Central Europe the face 

 markings are more extensive, and both they and the under-fur are whiter .. 



Fauna of New Zealand.f — F. W. Hutton has edited a valuable 

 ' Index Faunas Novas Zealandiae,' in which, with the help of numerous 

 collaborateurs, he has furnished a list of the animals inhabiting New 

 Zealand and the neighbouring seas. It has been a labour of love for all 

 concerned, and will doubtless have its reward in an increased knowledge 

 of the fauna of New Zealand. These balance-sheets are of the greatest 

 value, and the editor deserves congratulations. In the introduction there 

 is a discussion of the elements of the fauna, and sufficient evidence is 

 adduced to show, if that were necessary, that New Zealand is not an 

 oceanic island. 



Plankton of Gulf of Trieste. J — A. Steuer notes the following as 

 distinctive features : — larval stages of worms and crabs, plankton forms 

 limited to coast regions ; medusa swarms in more or less abundance ; 

 absent or sporadic in appearance : — Noctiluca, Thalasskola, colonial 

 Eadiolaria, Sapphirinaa, Ostracoda, Hyperiae, Pteropoda, Salpidas, which 

 are common or more frequent in the South Adriatic. The presence of 

 Pteropoda and Salpaa is due to periodical swarms in the South Adriatic 

 or to the perennial plankton of the south. 



Tunicata. 



Self-Fertilisation and Cross-Fertilisation in Solitary Ascidiansi 

 S. Gutherz has made experiments with Phallusia mammillata and Ciona 

 intestinal is, and finds that in the former artificial autogamy is successful 

 in all or almost all eggs, while in the latter it succeeds in only a small 

 percentage of cases. In both cases [cross-fertilisation was almost in- 

 variably successful. In natural conditions cross-fertilisation must be the 

 rule in Ciona, and autogamy exceptional ; in Phallusia the opportunities 

 for natural autogamy seem to be much greater. 



INVERTEBRATA. 



Mollusca. 



Egg-Envelopes of Cephalopods and Chitonida3.|] — A. Schweikart 

 finds that in five species of Chitonidaa the ovum is first surrounded by 



* Ann. Nat. Hist., Ixxvii. (1904) pp. 388-95. 



t Index Faunas Novre Zealandise. Published for the Philosophical Institute of 

 Canterbury, New Zealand. London (1904) 372 pp. 

 % Zool. Anzeig., xxvii. (1903) pp. 145-8. 

 § Arch. Mikr. Anat., lxiv. (1904) pp. 111-20. 

 || Zool. Jahrb., 1904, Supplement, Band iii. Heft 2, pp. 353-406 (4 pis. and 2 figs.). 



