December 22, 1905.] 



SCIENCE. 



841 



ters that depend on some other relation in the 

 germ cells than that brought about by the 

 shifting of the chromosomes in the reduction 

 division to produce ' pure ' gametes. 



Ziegler's failure to give a satisfactory ac- 

 count of sex determination on the differential 

 chromosome basis raises the wider question as 

 to whether at the present time we are really 

 obliged to look in this direction for a solution 

 of the question. The known facts in regard 

 to sex indicate that we have to deal with two 

 sharply contrasted, yet interchangeable states. 

 Furthermore, the facts seem to indicate that 

 some internal mechanism exists that gives 

 with great precision the one or the other con- 

 dition. We lack completely at present the 

 necessary knowledge of the chemistry of the 

 cell on which alone we can hope to establish a 

 real theory of sex determination. It might be 

 possible indeed to invent a purely fictitious, 

 quasi chemical, hypothesis, such, for instance, 

 as assuming that the female and the male 

 represent two contrasted conditions of the 

 same protoplasm, one state being a combined 

 (the female) and the other a separated (male) 

 condition of the aggregate bodies (molecules) 

 of which the protoplasm is composed. While 

 we might, were it worth while, work out this 

 or some similar idea into a more or less con- 

 sistent hypothesis, the only value that such a 

 conception might have at present would be 

 to indicate that sex determination may not be 

 the result of differential nuclear divisions that 

 locate sex determining chromosomes in differ- 

 ent cells, but that the process is chemical 

 rather than morphological. 



T. H. Morgan. 



Columbia University. 



the sargasso fish not a nest-maker. 

 Ever since 1872 the sargasso fish (Ptero- 

 phryne histrio) has been famous as the builder 

 of a remarkable globular nest made of the 

 sargasso weed, in the midst of which it finds 

 a congenial home. Professor Louis Agassiz 

 first described such nests observed by him in 

 December, 1871, during a voyage to Brazil 

 and attributed them to the Antennariid. 'No 

 one has since doubted the accuracy of the 

 identification, and in innumerable works it 



has been accepted as well established. A few 

 weeks ago, however. Dr. Hugh Smith, deputy 

 fish commissioner, informed me that he had 

 obtained eggs laid by the sargasso fish and, 

 on a visit to his office, he showed me some 

 under a microscope, and I was surprised to 

 find that they were quite different from those 

 found in connection with the nests and which 

 had been elaborately described by Vaillant and 

 Mobius. Later I received a letter from Pro- 

 fessor E. W. Gudger, of the State Normal 

 College of North Carolina, containing an ac- 

 count of the pterophryne's oviposition. This 

 corresponds remarkably with that practised by 

 the fish's distant relative, the angler {Lophius 

 piscatorius) . The elaborate provision thus 

 made specially for the eggs, as well as the ab- 

 sence of polar filaments, negatives the attribu- 

 tion of such eggs to the nest-maker of the 

 sargasso sea and leaves the question of the 

 real maker an unsolved problem. Similar 

 eggs were found free on the surface of the 

 sea off the African coast and noticed by Cun- 

 ningham (1887) but not identified. Can such 

 be the product of a flying-fish ? 



The fish, whatever it may be, is probably not 

 a direct maker of the nest but the filaments 

 of the eggs may, perhaps, become mechanically 

 entangled with the fronds as well as with each 

 other and the contraction into a subglobular 

 mass may be the result. 



Professor Gudger's communication is here- 

 with submitted. 



Theo. Gill. 



a note on the eggs and egg-laying of 

 pterophryne histrio, the gulfweed fish. 



Specimens of the gulfweed fish occasionally 

 drift with the Sargassum into the harbor of 

 Beaufort, N. C, and are picked up along the 

 beach by boys and brought to the laboratory 

 of the United States Bureau of Fisheries. 



When I reached the laboratory about the 

 middle of June, 1903, there were two of thepe 

 interesting fishes confined in an aquarium of 

 running salt water. These were put in my 

 care and on one of them and its eggs the 

 following observations were made. The two 

 fishes were of unequal size and were contin- 



