ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
113 
y. General. 
Natural Selection and Separation.* — Mr. A. E. Ortmann attempts 
to show that only separation can effect differentiation of species. He 
thinks we should distinguish four factors — (1) all organic beings vary ; 
(2) these variations may be transmitted to descendants ; (3) upon the 
material produced by variation and inheritance there acts Natural 
Selection. But (4) Natural Selection does not form species ; it only 
preserves or transforms already existing species. “ Different species 
are formed by bionomic separation ; separation does not always imply 
differentiation of the conditions of life, and accordingly does not always 
form new species ; but if there is a differentiation into species it is 
always due to separation under different bionomic conditions.” 
Specific Characters.! — Prof. R. Meldola, in his annual address to the 
Entomological Society of London, took occasion to discuss the utility of 
specific characters and physiological correlation ; dealing, that is, with 
a question which was the subject of lively discussion during the year 
1896. 
Prof. Meldola’s object was to suggest that physiological correlation 
may profitably form the subject of experimental investigation. He very 
justly remarks that, at present, discussions as to which out of a group of 
correlated characters is to be regarded as the cause of the survival of a 
living being are likely to prove barren. His hope is that his remarks may 
bring about a closer rapprochement between systematists and physio- 
logists. 
Nocturnal Protective Coloration.* — Prof. A. E.Verrill points out that 
very little attention has been paid to the colours of animals, as seen by 
twilight, moonlight, and starlight. Yet many animals only move by 
night, and those that roost in trees, bushes, or reeds need to be protected 
against their foes. When looked for, it is expected that instances of 
nocturnal protective coloration will be found to be numerous. The 
author cites a few examples, and concludes that the colours have been 
acquired by natural selection in consequence of the protection that they 
afford. 
Explorations in the Moluccas and in Borneo. §— Prof. W. Kfiken- 
thal has much to record concerning his visit to tho Malayan region in- 
1893-94. The detailed description of the collections made will be given 
in special monographs ; the first part is a general Beisehericht. 
The plankton of the Indian Ocean was studied during the voyage. 
Careful observations were made of the flying-fishes, and led to the con- 
clusion that they do move their pectoral fins a little, but only so as to 
alter their course. 
In the littoral region of Ternate, three zones were well marked : — 
(1) The region of coral reef and sea-grass, very rich in species, but less 
thickly peopled than the arctic littoral region ; (2) the almost lifeless 
* Proc. Amer. Phil. Soc., xxxv. (1896) pp. 175-92. 
t Trans. Entomol. Soc. Loncl., 1896 (1897) pp. lxiv.-xcii. 
f Amer. Jouru. Sci., iii. (1897) pp. 132-4. 
§ ‘ Ergebnisse einer zoologischen Forschungsreise in den Molukken und in 
Borneo.* I. Reisebericht. Abh. Senckenberg. Ges., xxii. (1896) 321 pp., 63 pls. r 
4 maps and 5 figs. 
1897 i 
