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SCIENCE 



[N. S. Vol. XXXVII. No. 946 



in question is not very well known, even from 

 the botanical standpoint. It was described 

 from Sonera by Asa Gray in 1855 as Thur- 

 heria thespesioides, and has also been identi- 

 fied with another Mexican species published in 

 1824 under the name Ingenhouzia triloha. 

 But this generic name was preoccupied, an 

 East Indian plant of another family having 

 been named in honor of Ingenhousz in 1818. 

 Nor is it certain that the Mexican Ingen- 

 houzia triloha represented the same species 

 that grows in Arizona. The flowers of the 

 latter are white, while those of the Mexican 

 species are described as yellow. 



It is true that the characters supposed by 

 Gray and Bentham to be of generic impor- 

 tance do not serve to distinguish Thurheria 

 from Gossypium. The cells of the capsule 

 show the same numbers, 3 or 4, as in many 

 kinds of cotton, and some kinds of cotton 

 imitate Thurheria in having a row of hairs 

 on the inside of the carpel. But Thurheria 

 offers more essential differences in the simple 

 involucral bracts, the expanded corolla, and 

 the absence of lint from the seeds, which are 

 covered only with a thin, short fuzz. In view 

 of these facts Gray's name may be retained. 



Some attention has been given to Thurheria 

 for the last three or four years in connection 

 with the cotton-breeding work of the Depart- 

 ment of Agriculture, because it seemed to be 

 the nearest relative of the genus Oossypium. 

 In external appearance and general behavior 

 it is closely similar to some of the shrubby 

 perennial types of cotton. The leaves are 

 narrow and deeply divided like those of the 

 so-called " okra " varieties of Upland cotton. 



Until the present season the study of Thur- 

 heria has been limited to greenhouse and gar- 

 den plants. The desirability of observing the 

 habits and variations of the species in the wild 

 state has been recognized, but all the locali- 

 ties where the plant was formerly known to 

 exist were rather inaccessible. New localities 

 on the slopes of the Santa Catalina Mountains 

 not far from Tucson, Arizona, have been dis- 

 covered recently by Professors Geo. F. Free- 

 man and J. J. Thornber, of the University of 

 Arizona, and one of these localities was visited 

 a few weeks ago through the courtesy of Mr. 



Harold Bell Wright, who is a collaborator in 

 the breeding work of the Bureau of Plant 

 Industry. In a small canyon about two dozen 

 large shrubby plants of Thurheria were found. 

 Some of them might even be described as 

 small trees, attaining a height of 10 feet, with 

 hard woody trunks an inch in diameter. Six 

 definite rings of annual growth are shown on 

 one specimen. 



The presence of punctures like those made 

 by the boll-weevil on some of the seed capsules 

 led to further search for the cause of the in- 

 jury. At first only a few larv® or pupae could 

 be found, embedded among the seeds of the 

 nearly mature capsules, but finally a capsule 

 containing an adult weevil was discovered by 

 Mr. Wright. As all the plants had passed the 

 flowering stage there was no means of learn- 

 ing whether the insect breeds in the floral 

 buds as well as in the seed capsules, but it 

 seems to be a habit of Thurheria to flower and 

 fruit for only a short time in September and 

 October. This habit of fruiting would not 

 allow more than one or two broods of weevils 

 to develop in each season. 



Cotton is much more susceptible to weevil 

 injury because it produces buds and bolls 

 through a much longer period, thus providing 

 facilities for breeding several generations of 

 weevils. The fact that Thurheria is so much 

 better adapted to escape serious injury may 

 mean that it is the original host of the boU- 

 weevil. Otherwise the infestation of Thur- 

 heria at Tucson must be explained by refer- 

 ence to prehistoric cotton cultures, which 

 might have brought the weevil in from Mexico. 

 The Pima Indians of Central Arizona culti- 

 vated an indigenous variety of cotton until a 

 few decades ago, and the Hopi Indians of New 

 Mexico still raise a little of their native cotton 

 for ceremonial purposes. That the weevils in 

 the Santa Catalina Mountains represent a 

 recent importation from Texas seems alto- 

 gether improbable. 



As no cotton is now grown in the region of 

 Tucson, the existence of weevils in the wild 

 Thurheria is of no direct agricultural interest. 

 But it is obviously desirable to know more of 

 the habits and distribution of Thurheria in 

 Arizona and adjacent states. A rapid exten- 



