NATURE OF THE DRACUNCULUS, OR GUINEAWORM. 131 
be endemic in the hot season in dry arid tracts, some during the rains in low moist 
situations, and some peculiar to the cold or winter months. We have hardly a reason 
for concluding, as appears to have been taken for granted by Dr. Chisholm and all sub- 
sequent writers, that the disease of Grenada, which appears there during the winter, is 
the same as that which appears in the East Indies during the rains, however the general 
form of the animals that occasion the disease in both cases may correspond." We have, 
unfortunately, but little evidence bearing upon this opinion*, but what little we have 
seems to lend it support. How else can we account for the great difference in size 
usually attained by mature individuals in different countries? Thus, the average length 
of specimens of Dracunculus in Bombay and India generally, seems to be from twenty- 
six to thirty inches, or even less. Mr. Carter, who has had so much experience, says 
he has never measured one exceeding thirty-two inches inlength. In Egypt, according 
to Clot Bey, they vary from six inches up to four feet in length, whilst, as far as I have 
been able to ascertain, all the very long worms, from eight to twelve feet, have been 
African t. 
In all probability, the specimens of Guineaworm examined by Mr. Busk were African, 
since he says, ** In every instance that has come under my notice I have found that the 
length of the worm has nearly reached, and in some instances has exceeded, six feet.” 
Should this be the case, it may perhaps account for the difference before alluded to in 
the anatomy of the worms he has described from what I have met with in specimens 
from Bombay. 
Then, again, are the Guineaworms that have been met with in Horses} and Dogs§ of 
the same species as those which infest the human subject ? 
In conclusion, I would refer to the great difference observed, in various countries, and 
in different parts of India, in the times of the annual epidemie prevalence of the disease 
* I think perhaps it may be well to record here the three statements of difference in the external characters of 
worms that I have met with in different writers; for although no great stress can be laid upon them, they might, by 
drawing attention to already observed peculiarities, assist in the determination of this question. 
“Respecting the structure of a worm which M. d'Obsonville extracted from his own leg, Bingley quotes that 
author. The body was not thicker than a strong thread; but when the animal was extracted, it was found to be of 
the length of two or three ells. Its head was of a chestnut colour, and to the naked eye it appeared to ووس‎ "T 
small black point. On examining it with a common magnifying-glass, it appeared to be سي‎ ey ya — 
rings, united to each other by an exceedingly fine membrane ; and a single intestine extended through the body.’— 
Trans. of Calc. Med. & Phys. Soc., vol. i. (1825) p. 157. : : 
“The worm was of equal volume till within the last inch, when it became a very little larger, was spirally indented, 
and ended in a small hooked point.” —W. Scott, Edin. Med. & Surg. Journ., vol. xvii. p. 96. ; 
“The tail is attenuated to a very sharp point, and bent like the point of a cobbler's awl. It is also ormai with a 
Jew rough points. . . . Some, however, are without these points, having the tail smooth.” —M" Clelland, < ui : 
T The most trustworthy account I have met with of this great size attained by the Guineaworm 15 in a "reta 
de Dracunculo," by Gallandat (Nova Acta Acad. Nat. Curios., vol. v. (1773) Append. p. Ree pln eo dM 
he had himself been to the coast of Guinea and seen what he describes, says 7 ndi animal, nod موص ا‎ aim 
novem, decemve, un- et duodecim pedum longitudinem sequat, extrahitur prudentissime volviturque circum laminam 
ligneam ut facilius exeat.” 
+ Forbes, Madras Quart. Journ. of Medical Science, 1839. 
$ Dr. Smyttan, Trans. of Med. & Phys. Soc. of Calcutta, vol. i., 1825. 
