350 ' BOTANICAL GAZETTE [October 



but many of them are not true gall-makers while others produce very small and 

 insignificant galls. In a third paper 19 the same author describes three new 

 species of dipterous gall-makers, and in the fourth 30 he describes four new 

 species of gall midges from St. Vincent, West Indies. The development and 

 structural characters of all these galls remains to be worked out by the botanist. 

 Beutenmuller 31 has given us another most excellent paper on the North 

 American galls. This last paper is on the genus Dryophanta, and contains 

 excellent descriptions of both galls and insects of the 39 known species, with 

 complete synonomy and bibliography. Most of the galls are figured, and all 

 of them occur on oaks, but in a few cases the specific name of the host is not 

 known. The 32 species for which the hosts are given are found on 24 species 



w 



of oak. Quercus rubra leads with 7 species, Q. alba has 5, Q. coccinea has 4, 

 Q. undulata, Q. velutina, and Q. nana have 3 each, Q. arizonica, Q. marylandica, 

 Q. prinoides, Q. palustris , and Q. laurifolia have 2 each. Dryophanta palustris 

 is found upon 7 different hosts, D. lanata on 5, D. notha on 3, 5 other species 

 on 2 each, and 24 species on 1 each. 



The same author 32 also describes and figures two new species of Holcaspis 

 galls from Mexico. These papers will be absolutely necessary for students 

 who wish to make botanical studies of cecidia. 



One of the most interesting and important contributions to American 

 cecidology is by Erwin F. Smith, 33 who has continued his studies on crown 

 gall of plants, and presents some interesting comparisons with the cancer of 

 human beings. The similarity between plant and animal malformations has 

 attracted the attention of many observers, who have looked upon the study 

 of plant galls as a fruitful field of investigation, but unfortunately very few 

 have gone into it far enough to see the real possibilities. Smith's confidence 

 in this line of work is expressed as follows: "I believe we have in these par- 

 ticular plant overgrowths a key to unlock the whole cancer situation. In 

 consideration of these discoveries many closed doors in cancer research must 

 now be opened, and studies on the etiology of the disease must be done over 

 with a view to finding a parasite within the cancer cell, and separating it 

 therefrom by an improved technic of isolation." In answer to his critics he 

 claims that the crown — fl ^ — * * >1 * *- ~* + k ~ •mm«l. He 



also shows that the tendency of the human cancer to form secondary growths 

 by means of strands of tissue is similar to the formation of secondary growth 



IQII 



29 Felt, E. P., Three new gall midges. Jour. N.Y. Entom. Soc. 19: i^ 1 ^- 



30 



, New West Indian gall midges. Entomol. News 9$lt73r^7S* J 9 12, 



their galls. Amer 



Vmerican 



32 . Two new species of Holcaspis from Mexico. Psyche 18:86, 87. i9 12 - 



33 Smith, Erwin F., On some resemblances of crown gall to human cancer. 

 Science N.S. 35:161-172. 1912. 



