926 



SCIENCE 



[N. S. Vol. XXXII. No. 834 



concerned, also by Hubrecht and by Regan. 

 Doubtless a similar view is held by other ich- 

 thyologists at the present time. 



The arrangement of the fishes continued to 

 exercise Agassiz during succeeding years. 

 In ISSS'^ he read a communication before the 

 American Academy of Arts and Sciences ad- 

 vocating the classification of fishes by the 

 structures of the mouth as related to the 

 facial bones. And as late as 1867 he again 

 occupied himseK with fishes, reading, in that 

 year," a paper on the classification of the 

 catfishes. 



In the light of present knowledge this classi- 

 fication of the catfishes was not a happy one. 

 He regarded the group as " an order of ganoid 

 fishes which should be placed between the 

 sturgeons and the garpikes." He based this 

 view, he tells us, on resemblances in the brains 

 of the catfish and the sturgeon; but he seems 

 to have been unduly impressed by the South 

 American armored catfishes. To be sure such 

 forms as Loricaria and Plecostomus are in 

 some regards suggestive of the sturgeon; but 

 the resemblances are now looked upon as mere 

 parallelisms and not as signs of relationship. 



In conclusion: Louis Agassiz deserves 

 greater credit for his later than for his earlier 

 classification of the fishes. He sought to 

 base it on facts of anatomy and embryology 

 and not, as with the earlier classification, on a 

 single superficial character. And in ranking 

 the groups as classes and in raising the 

 selachians, eyclostomes and fishes proper, to 

 equivalent rank, he was the forerunner of our 

 modern views. 



L. HUSSAKOP 



^ TBE SYNTHESIS OF FOEMALDEEYDE BY 

 LIGHT WITHOUT CHLOROPHYLL 



Eeaders of Science will be interested in the 

 achievement by chemists of the duplication of 

 the first step in the synthesis of carbohydrates 

 by plants. Many years ago it was found that 

 formaldehyde, when made slightly alkaline, 



' Proceedings Academy Arts and Sciences, IV., 

 p. 108. 



'Proceedings Boston Society Natural History, 

 XL, p. 354. 



transformed itself spontaneously by a series of 

 condensations into a mixture of sugars called 

 " f ormose," but the first step in the process of 

 the synthesis of the sugars, namely, the syn- 

 thesis of formaldehyde from carbon dioxide 

 and water with the liberation of oxygen it has 

 been impossible to achieve under conditions at 

 all comparable to those prevailing in plants. 

 This synthesis has now been obtained by 

 Berthelot and Gaudechon^ by means of ultra- 

 violet light. 



A mixture of carbonic anhydride and water 

 under the influence of these rays liberates 

 oxygen and produces carbon monoxide and 

 formaldehyde. Carbon monoxide and water 

 so illuminated produce carbon dioxide, carbon 

 monoxide, hydrogen and formaldehyde. 



Moreover, glucose under similar conditions 

 gives rise, among other things, to marsh gas, 

 hydrogen and carbon dioxide. 



It seems not impossible, in view of these 

 facts, that the role of the chlorophyll may be 

 the transformation of the longer wave-lengths 

 of light to shorter more active ones, thus act- 

 ing in a photodynamic way, as frequently 

 suggested. 



A. P. Mathews 



/ 



SPECIAL ARTICLES 



NOTE ON THE DISTRIBUTION OF SOME PENNSYL- 

 VANIA FISHES 



While angling at Valley Forge, on Sep- 

 tember 27, 1910, I caught a number of small 

 fishes in Valley Creek, a tributary of the 

 Schuylkill River. As several of these have 

 not been found before so far to the east in 

 Pennsylvania, I take this opportunity of re- 

 cording them. These are Pimephales notatus 

 and Exoglossum maxillingua. Along sloping 

 shores in shallow water were very numerous 

 large schools of small fishes, which I found to 

 be mainly the young of the preceding, though 

 Ahramis crysoleucas, Notropis iifrenatus, N. 

 cornutus, Fundulus diaphanus, Lepomis au- 



"■ " Synthfise photocliemique des hydrates de car- 

 bone aux dSpens des elements de I'anhydre car- 

 bonique et de la vapeur de I'eau en I'absence de 

 ehloropliyll, etc.," Comptes Rendus de I'Acad. de 

 Sci., 150, 1910, p. 169. 



