October 3, 1884. 



SCIENCE 



339 



cannot be likened to blushing, but are evidently 

 under the fish's control, and are intelligently 

 used to its advantage. 



The bony gar (Lepidosteus osseus) is an- 

 other fish haying decided control over the col- 

 oration of its scales. When this fish is at rest, 

 the scales are pale blue, with a pink margin ; 

 and about the head and gill-covers there is a 

 variety of brilliant hues. At times all these 

 colors will suddenly disappear, and the fish has 

 much more the appearance of a water-soaked 

 stick than of a living animal. Unfortunately 

 I have had too few opportunities for observing 

 this species to determine the reasons for these 

 changes ; but it is evident that they are under 

 the control of the fish, and therefore advan- 

 tageous. 



The common pike (Esox reticulatus) also 

 exhibits a variation of coloring, under different 

 circumstances, and suggests the same facts that 



have already been stated with regard to other 

 species. 



When the chief aim of biological science 

 seemed to be the naming and describing of 

 ' species,' it was found that no description of 

 the color of a fish, unless very unusual and 

 marked, was at all satisfactory. Considering 

 the subject of color, as I have in this article, 

 the cause is very evident. 



In an early number of Science, I offered 

 many reasons for believing that fishes were 

 very far from spending as joyless, machine-like 

 an existence as has been supposed. Those 

 reasons I supplement with the results of studies 

 of their habits, with reference to their brilliant 

 tints and sombre hues, and am in accord with 

 Mr. Romanes when he states that we are jus- 

 tified in regarding ' the presence of a color- 

 sense in them as axiomatic' 



Charles C. Abbott. 



AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. 



PROCEEDINGS OF THE SECTION OF 

 BIOLOGY. 



A large number of papers (forty-three in all) were 

 presented before the section of biology, but we regret 

 that in our limited space we can give merely the 

 briefest outlines. The first we may mention was a 

 paper by Mr. H. GT. Beyer, on the influence of oxy- 

 genated and unoxygenated blood, as well as of blood 

 in various degrees of dilution, on the isolated heart of 

 the frog and terrapin. The paper aimed to prove that 

 it is not concentrated mammalian blood which pro- 

 duces the greatest amount of work done in either 

 the heart of the frog or that of the terrapin, but a 

 certain degree of dilution is necessary. There is no 

 exception in the constant, stimulating influence in 

 oxygenated blood, and none in the depressing effect 

 of non-oxygenated blood. 



Dr. C. S. Minot read a paper on biological prob- 

 lems. The author opposed the trinomial system, and 

 considered the present mode of determining species 

 entirely unscientific, and thought that the species 

 should be based on a statistical study of all the vari- 

 ations that are known to occur. Individuals are not 

 always homologous. The only fixed units are, 1° 

 cells ; 2° the whole series of generations of cells from 

 a single ovum, — a cell-cycle. An individual may be 

 almost any fractional part of a cell-cycle. Roughly 

 speaking, the higher the organism, the fewer the 

 number of individuals it comprises. The author 

 considered the ovum to be homologous with the en- 

 cysted protozoon, the zona radiator being equivalent 

 to the capsule or cyst of the protozoon, and the con- 

 tents also homologous. 



In a paper by Lillie J. Martin on a botanical study 

 of the mitegall found on the petiole of Juglans nigra, 



known as Erineum anomalum Schw., a general sur- 

 vey of the gall was given, as to position, number, 

 general appearance, etc. This was followed by a 

 description and comparison of the microscopical ap- 

 pearance of the gall and normal petiole, concluding 

 with the supposition that the mite entered at an early 

 period in the life of the petiole, and the growth of 

 the gall was from within outward. 



A paper by Prof. B. G. Wilder, on the relative 

 position of the cerebrum and the cerebellum in an- 

 thropoid apes, was illustrated by photographs, and a 

 preparation of a chimpanzee's brain; conclusively 

 settling the much-disputed point, as to whether the 

 cerebrum extended over the cerebellum or not, as 

 the cerebrum was seen to extend at least a milli- 

 metre over the cerebellum. 



Mr. E. D. Cope, in a paper on the phylogeny of the 

 artiodactyle Mammalia derived from American fossils, 

 considered the derivation of the seledont dentition 

 from the bunodont as established from a mechanical 

 point of view. The oldest American artiodactyl 

 (Pantolestes) is bunodont. The modification pro- 

 ceeded as in other ruminant lines by the co-ossifica- 

 tion of the bones of the legs and feet. The peculiar 

 structure of the carpus in the Oreodontidae shows 

 them to be, without doubt, the ancestors of the Tra- 

 gulina. The following table represents the present 

 views of the author on this subject. 



Tritubercular Bunodontia (Pantolestidae) . 



Selenodontia. 



Quadritubercular Bunodontia. 



Hyopotamidae. 

 I 

 (?) Pecora. 



Oreodontidae. 



I 

 Tragulina. 



Poebrotheriidae 



I 

 Tylopoda. 



