552 



SCIENCE. 



[X. S. Vol. XXI. Xo. 5."6. 



might have built up these elevations, and 

 what causes might have operated to depopu- 

 late them. For if mound-building ants now 

 live both in Texas and in Montana, it is hardly 

 necessary to call in climatic changes to ac- 

 count for the facts. 



In California there are extensive tracts of 

 similarly appearing mounds (vulgo ' hog- 

 wallows ') in the San Joaquin valley; but here 

 not only can their wind-drift origin be sub- 

 stantiated by ocular demonstration during any 

 of the frequent sandstorms, when the sage- 

 brush clumps are often left two feet above 

 the general level because their roots resist the 

 eroding action by holding the sand; but the 

 wind-drift origin of the general soil surface 

 can mostly be verified, even when, as fre- 

 quently happens, the bushes thus left ' high 

 and dry ' die out in the course of time, and 

 subsequent aqueous erosion increases the 

 height, and a gradual consolidation of the 

 material occurs. 



' Hogwallows ' of quite different origin oc- 

 cur in Washington, on the gravelly lands south 

 of Tacoma city, e. g., on Yelms prairie. Here, 

 in the land of almost daily heavy rains during 

 certain seasons, water erosion has removed 

 the sand and smaller gravel from variously- 

 shaped areas surrounding one or several larger 

 blocks (erratics), the channels between ad- 

 jacent mounds being lined with cobbles left 

 behind by the water. Yet while the general 

 aspect of the surface is similar to that of the 

 ' hogwallows ' of California and the mounds 

 of the Calcasieu prairie, there is clearly no 

 genetic relation between the three kinds of 

 ' mounds,' however similar in their external 

 conformation. E. W. Hilgard. 



Berkeley, Cal., 

 March 10, 1905. 



PROGRESS IN THE STUDY OF THE KELEP. 



The existence of an efficient insect enemy 

 of the boll weevil having been ascertained, it 

 became necessary to determine also the extent, 

 if any, to which it could be utilized in the 

 United States. Since the last published re- 

 port on the subject* many additional data 



* ' Report on the Habits of the Kelep,' Bull. 49, 

 Bureau of Entomology, U. S. Department of Agri- 

 culture, 1904. 



have accumulated, but there are three fea- 

 tures worthy of special notice. 



The Kelep in Western Guatemala. — Recent 

 letters from Mr. W. R. Maxon report the ex- 

 istence of the kelep in the cotton fields of the 

 Retalhuleu district of western Guatemala. 

 Mr. Maxon has also sent to the Department 

 of Agriculture seeds and dried bolls of an 

 upland cotton of a variety evidently similar 

 to that grown by the Kekchi Indians of Alta 

 Vera Paz. The three nectaries inside the 

 bracts appear to be even larger than in the 

 Kekchi cotton. The pair of inner stipular 

 bracts which subtend each of these nectaries 

 are the largest yet known, and have their 

 margins fringed with long hairs, as though 

 to increase their efficiency in holding the 

 nectar to attract the keleps inside the in- 

 volucre. 



This west Guatemalan or so-called Pachon 

 cotton is also an annual crop and is said to 

 ripen in five months, or in even less time than 

 the Kekchi. Following the analogy of other 

 plants, these varieties, if they can be accli- 

 matized in the United States, may be ex- 

 pected to mature in a still shorter period, 

 which gives them distinct agricultural in- 

 terest. The effectiveness of the plan of miti- 

 gating the injuries of the boll weevil by cul- 

 tural means depends upon the shortening, as 

 far as possible, of the growing season of the 

 cotton plant. Other things being equal, a 

 short-season variety will also be an early 

 variety, of course, but the simultaneous plant- 

 ing of quick-growing vai'ieties is likely to 

 prove a better measure of protection than un- 

 certain and desultory early planting, because 

 the weevils are much more likely to perish by 

 starvation after the weather is warm enough 

 to bring them to the condition of activity than 

 while they are kept by the cold in a torpid, 

 hibernating state. It is thus not impossible 

 that these short-season varieties of cotton 

 which are cultivated in Guatemala by the help 

 of the kelep may prove to be of value in the 

 United States, even without their insect guard- 

 ians. It may be repeated, too, that both of 

 the dwarf, kelep-protected varieties of Guate- 

 mala belong to the upland type and produce 

 fiber of good length and quality. 



