68 



SCIENCE 



[N. S. Vol. XXXI. No. 785 



Me. L. a. Boeeadaile, M.A., of Selwyn Col- 

 lege, has been appointed university lecturer in 

 zoology at Cambridge University. 



DISCUSSION AND CORRESPONDENCE 

 J COTTON ANTHEACNOSE 



Since Dr. Atkinson's work on cotton 

 anthracnose, 1890-3, little has been done on 

 this now important disease. Recent work here 

 has brought out some very interesting points 

 which in a way confirm some of Dr. Atkin- 

 son's theories in connection with the infection 

 of seed and seedlings. Last winter while 

 working with seed taken from a field where 

 the disease occurred the previous summer, I 

 found anthracnose occurring in a number of 

 germination tests. This led me to search for 

 the fungus in the tissue of the seed. I found 

 that by taking bolls which were slightly dis- 

 eased and mature it was an easy matter to find 

 the fungus filaments beneath the seed coats 

 and in the tissues of the cotyledons. The 

 spores of the fungus are also readily found 

 between the seed coats and the cotyledons of 

 mature seed. Numerous inoculation experi- 

 ments during the past summer show that the 

 fungus seems to prefer the seed and lint to 

 other portions of the plant. In fact, in some 

 cases the attack is confined to these parts, 

 there being no sign of the disease on the walls 

 of the bolls. In some cases where the bolls 

 mature and the cotton opens out with no sign 

 of disease other than slight discoloration of 

 the lint, the fungus will be found on such lint 

 and in the seed. Such seed, of course, when 

 planted produce diseased seedlings and thus 

 spread the disease. This season numerous out- 

 breaks of anthracnose in various sections of 

 this state have been traced to diseased seed. 

 Some of these occurred where cotton had 

 never been planted before. From an economic 

 standpoint this phase of the problem seems to 

 be very important. The south is now sustain- 

 ing a loss of millions of dollars annually from 

 anthracnose. It has been estimated that the 

 state of Georgia loses over $14,000,000 an- 

 nually and a very conservative estimate of the 

 loss of South Carolina would be from $400,000 

 to $500,000 annually. 



Since the twentieth of last July I have been 

 unable to isolate the fungus from the fields 

 where cotton was planted last year. From 

 this it seems that a one year's rotation with 

 disease-free seod might eliminate the disease. 



Interesting results have also been obtained 

 in reference to seed treatment, method of in- 

 fection of the bolls, resistance of different 

 varieties of cotton, breeding resistant strains, 

 etc., all of which will be published at an early 

 date in report of the South Carolina Experi- 

 ment Station. H. W. Baeee, 



Botanist 



South Caeolina Expekiment Station 

 October 26, 1909 



metaphysics and mendelism 

 There are reasons for regarding man as a chim- 

 panzee on which an additional element, " man- 

 ness," has been superposed. There you have man 

 expressed or explained in terms of his anthropoid 

 ancestor. The characters of a frog are undoubt- 

 edly latent in the frog's tadpole. What is to 

 hinder, therefore, expressing or explaining the frog 

 in terms of the tadpole by saying the tadpole 

 carries the characters of the frog? The logic is 

 sound in the statement that the tadpole contains 

 frog factors or " frogness." The question is merely 

 as to the helpfulness of sound logic used that 

 way.' 



The helpfulness of sound logic, aside from 

 its use as a mental discipline, is usually based 

 on its relevance to the matter under discus- 

 sion. As regards the chimpanzee we shall 

 doubtless all agree with the learned Cali- 

 fornian if he will advance scientific proof that 

 in homo-simian hybrids " chimpanzeeness " 

 and " manness " behave toward each other in 

 Mendelian ratio; for it is Mendelian inherit- 

 ance, it must be remembered, that the English 

 scientists are talking about. If the tadpole 

 contained the potentiality of developing either 

 into a frog or, let us say, a salamander, ac- 

 cording to circumstances under experimental 

 control, we might consider " frogness " as a 

 factor, the presence or absence of which would 

 have a determinative influence in development. 



' " The Hypothesis of ' Presence and Absence ' 

 in Mendelian Inheritance," W. E. Ritter, Science, 

 September 17, 1909. 



