ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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elements, derived partly from the attractive spheres, form a mechanism 
which determines the separation of the secondary chromosomes. 
The study of these facts led to the generalization that in all animal 
and vegetable cells there is an attractive sphere; and the truth of this 
has been confirmed by the studies of many observers of animal and plant 
life. M. van der Stricht has studied the sphere in the blastomeres of 
Triton and in the cartilaginous cells of various Amphibia. He inclines to 
the view that the nuclear vesicles of the reconstituted nuclei are formed 
by the fusion of the ends of the chromatic loops, but he does not make 
the assertion definitely. In Triton he finds that the division of the 
attractive spheres of the egg is effected, as a rule, in the quiescent stage 
of the nucleus, rarely during the anaphasis of the mother nucleus, and 
exceptionally during its metaphasis. Dr. Van der Stricht is satisfied 
that he brings forward sufficient information to justify a belief in the 
existence of attractive spheres in cartilaginous cells. 
7 . General. 
Protective Resemblance in the Animal Kingdom. 1 * — M. F. Plateau 
gives a general account of protective resemblance, and points out how 
general it is ; there are scarcely any animal forms that do not, at some 
period of their existence, have recourse to imitation. In temperate 
Europe we may meet, at every step, with cases not inferior to any 
presented in the tropics. These phenomena are not, however, the results 
of ratiocination ; it is in Man only that imitation with intent to deceive 
his neighbour is the result of the association of ideas. 
Voyage of the ‘ Albatross.’t — Prof. A. Agassiz has published a 
general sketch of the expedition of the ‘ Albatross ’ from February to 
May 1891, on the western side of America and to the Galapagos. Somo 
of the most striking passages are those in which the author deals very 
incisively with the claims of Prof. Haeckel to pose as an authority on 
pelagic work. The “zoological pope at Jena” is said to have had “ no 
experience whatever at sea of the sort of pelagic work which he so 
complacently condemns ex cathedra. The observations on the pelagic 
fauna, on which Haeckel prides himself, made as a passenger in an East 
India steamer, are, of necessity, like its phosphorescent track, somewhat 
superficial.” It is considered that Haeckel’s account of the distribution 
of the pelagic fauna and flora is premature, and as an accurate catalogue 
representing our knowledge is worthless. Prof. Agassiz points out 
that the number of new species constantly found by the tow-net of the 
* Albatross,’ when hauled from 200 fathoms to the surface, plainly shows 
that no reliance can as yet be placed on deductions drawn from tho 
comparison of the contents of the nets at different localities and at 
varying depths. The deep-sea fauna of the Panamic district was found 
to contain a number of West Indian types or east coast forms, but it 
is not as rich as the West Indian. This comparative poverty is 
probably due to the absence of a great oceanic current like the Gulf 
Stream, which brings a large amount of food. Considerable attention 
was given to the coloration of deep sea forms, and it is interesting to 
note that there is much diversity. 
* Bull. Acad. Roy. de Belgique, lxii. (1892) pp. 89-135. 
t Bull. Mus. Comp. Zool., xxiii. (1892) pp. 1-89 (22 pis.). 
