June 3, 1904.] 



SCIENCE. 



867 



tlieir outer walls are notably thickened. A 

 well-developed cuticle is present. 



It has been found that all of these serophilous 

 characters may be produced by growing the 

 plant in an undrained wet sphagnum sub- 

 stratum, whose temperature is maintained sev- 

 eral degrees below that of the air. This effect 

 is obtained even in subdued light. Further, 

 under these conditions the drops of oil or 

 resin, so characteristic of bog xerophytes, are 

 formed in the epidermis and the cells adjacent 

 to the bundles. Such resinous deposits occur 

 also in the plants grown on dry sand, but are 

 wanting under favorable moisture conditions. 

 It is believed that these modifications are, in 

 the case of the bog habitat, a response to the 

 unfavorable conditions for absorption by the 

 roots, occasioned by the low substratum tem- 

 perature and lack of proper aeration. 



That palisade tissues may be greatly in- 

 creased or developed in shaded conditions is 

 also evident. The experiments suggest that 

 even when such a response is obtained in 

 strong light, it is to be correlated with drouth 

 rather than with light. The increased trans- 

 piration brought about by direct insolation, 

 as it increases the temperature and decreases 

 the relative humidity of the air, would seem to 

 be an ef&cient cause for palisade development. 

 The elongated cells of the palisade, therefore, 

 appear to be an adaptation for the ready trans- 

 ferrence of food materials in the leaf tissues, 

 under the stress of a reduced water supply. 

 The analogy of dry sand habitats and un- 

 drained wet bog habitats is certainly indi- 

 cated. 



The details of these experiments and others 

 tending in the same direction will be published 

 elsewhere. Edgar N. Teanseau. 



UNrVEESlTT OF MICHIGAN, 



May 11, 1904. 



ALBHTO BROOK TROUT. 



Among the brook trout hatched at the 

 Adirondack Hatchery, Saranac Inn, IST. Y., 

 in March, 1902, there appeared to be some dis- 

 tinct albinos. There were about fifty of 

 these fry out of an entire hatching of 800,000 

 ordinary brook trout eggs, taken from both 



wild and confined trout. These albinos were 

 put by themselves, and four reached maturity. 



Two of them are typical albinos. They are 

 the same in outline as the ordinary brook 

 trout. The skin is white, mottled with an 

 ochraceous yellow, colored with the typical red 

 and yellow spots. The fins are white, with 

 the red band and yellow mottling. Eyes red. 

 The general appearance of the fish is delicate, 

 and the bones are apparently visible through 

 the seemingly transparent skin. As these fish 

 were reared in captivity they have be^n con- 

 fined to the ordinary fish races, and fed on 

 ground liver. One is a male, the other a 

 female. The former now measures seven 

 inches in length; the latter, nine inches. 



The other two fish are a grayish white, with 

 dark fins and black eyes. 



On November 10, 1903, when the two 

 albinos were twenty months old, they were 

 stripped for eggs and fertilization. At this 

 time their combined weight was approximately 

 one half pound, the female being much the 

 larger. Mr. G. E. Winchester, foreman of 

 the Fish Hatchery, made the following experi- 

 ments in fertilization : viz., first cross, 527 eggs 

 from female albino X albino male; second 

 cross, 103 eggs from female albino X natural 

 male; third cross, 424 eggs from natural fe- 

 male X albino male. 



The eggs, after fertilization, were placed in 

 the hatchery races the same as all brook trout 

 eggs. The hatching began March 1, 1904, 

 and continued until the thirteenth of the 

 month, the period of incubation being the 

 same as that of the ordinary brook trout egg. 



The result of the hatching was as follows : 

 From the first cross 32 hatched, or approxi- 

 mately 6 per cent. ; from the second cross 43 

 hatched, or approximately 42 per cent.; from 

 the third cross 416 hatched, or approximately 

 98 per cent. 



At the present time — one month after all 

 the fish were hatched — the following number 

 is living: from the first cross 20, or 62 per 

 cent.; from the second cross none; from the 

 third cross all, or 100 per cent. 



The weakness of the pure albinos is indi- 

 cated by the fact that only 6 per cent, of the 

 eggs proved fertile, and several of these are 



