May 24, 1924 
821 
Acromania, or “ Crazy-Top” 
the slight constitutional weaknesses, like those that may be detected when prog¬ 
enies are compared in plant-breeding work. With the existence of such dis¬ 
orders recognized, their relation to the problems of adaptation must be con¬ 
sidered. 
Though the occurrence of crazy-top may have no relation to the conditions 
that determine the growth and productiveness of the normal plants, it may be 
a serious factor in determining the values of varieties for purposes of production. 
The presence of a slight disorder, as of crazy-top in Pima cotton, under moderate 
conditions, might remain unrecognized, although rendering the crop much more 
sensitive to unfavorable conditions. The effects of the disorder would be con¬ 
sidered as a character of the variety, which would appear less suited to culti¬ 
vation, as when crazy-top was looked upon as a special weakness of Pima cotton. 
In the same way, it might be supposed that a field, or a farm, or a section of 
country was not well suited to cotton, while the crop in reality might be suffer¬ 
ing from a growth disorder rather than from any unfavorable soil conditions. 
If such a disease were carried over from year to year by survival of infested 
plants through the winter, the yields would be reduced and the necessity of 
a more frequent rotation with other crops would be inferred. The rotation 
might be desirable for other reasons, and less crazy-top might be encountered in 
a different field. It is reported that some of the worst cases of crazy-top have 
occurred on new land, but of course this does not prove that affected areas do 
not increase where cotton is grown continuously. 
CRAZY-TOP IN DIFFERENT VARIETIES OF COTTON 
The differences in crazy-top symptoms between the Pima and the Upland 
varieties are in line with what is known regarding the varied degrees of suscep¬ 
tibility of different types of cotton to other growth disorders. The theory that 
crazy-top is due to a special weakness or tendency to degeneration in Pima 
cotton must be discarded, in view of the fact that the Upland varieties are more 
seriously affected than the Pima, especially when grown under unfavorable con¬ 
ditions. The more extreme symptoms that appeared in the field of Hartsville 
cotton at Casa Grande have not been observed in Pima. 
Near Phoenix, Ariz., the symptoms of crazy-top were observed in adjacent 
plantings of Pima and Acala, under conditions of luxuriant growth, and there 
the disease reactions were more similar than would be inferred from the con¬ 
trasts that had been shown between Pima at Sacaton and Hartsville at Casa 
Grande. The characteristic crazy-top symptom in Pima, the strong upright 
branches at the top of the plant, had appeared to be lacking in the Hartsville 
variety at Casa Grande, but was shown quite distinctly in the Acala at Phoenix, 
though somewhat less pronounced than in the adjacent Pima rows. In this 
planting of Acala the growth of the main stalk was but little restricted, and the 
tendency to reduction and distortion of the leaves was much less apparent than 
in the Hartsville planting at Casa Grande, though in some plants it was definitely 
shown. Also many of the Acala plants had a tendency to abort the leaves near 
the top of the main stalk, thus forming tufts or spikes of very short branches 
bearing small squares, as shown in Plate 14. 
Also there was noted in Acala the same tendencies as in Pima to transform 
fruiting branches into vegetative branches, or to develop vegetative shoots from 
axillary buds of fruiting branches, with or without suppression of the terminal 
buds. 
In China the Upland cottons were more affected by the cyrtosis disorder than 
were the Egyptian and Sea Island cottons, but the native Chinese cottons, 
representing the Asiatic type, were more strikingly affected than the Upland 
