268 
Sat'coptic Scabies 
became quite fashionable as a subject for theses for the doctorate. Gerlach 
published his Krdtze und Raude in 1857; Fiirstenberg his Krdlzmilben der 
Menschen und Thiere in 1861; and Delafond and Bourguignon their Traite 
pratique in 1862. 
The fine works of Bourguignon, Gerlach and Fiirstenberg are generally 
regarded as the classical publications on this subject, and deserve a special 
notice. They present a remarkable variety of style and outlook. 
Bourguignon is a leisurely, elegant, philosophical—and it must be confessed 
sometimes prolix—writer, who works away patiently and indefatigably, 
without too much reference to what his contemporaries are doing, though 
he is learned on the ancient history of the subject. He anticipates incredulity 
for some of his results, but is prepared to stand by them. “ To us les faits que 
nous avan^ons ont ete vus cent fois avant d’etre definitivement admis, et 
comme beaucoup d’entre eux echapperont necessairement au premier abord 
aux entomologistes, qui seraient tentes de les verifier, car la grande habitude 
d’etudier le meme objet vous donne a la longue une habilete, qu’on n’aurait 
pas dans le principe serait-on le plus habile des observateurs, nous prions 
ceux, qui contesteraient la presence de tel ou tel organe, de nous permettre 
de leur fournir la preuve de son existence” ( Traite entomologique, p. 15). One 
cannot “say fairer” than that! 
He pays much attention to the dorsal armature, and to the skeletal 
structure of the legs and rostrum. He found and described the male, and 
observed the tocostome of the female, and altogether did remarkable pioneer 
work, though his details have in many respects been proved to be inaccurate 
by subsequent observers with more adequate instruments. 
His joint work with Delafond—the Traite pratique, published in 1862—is 
a comprehensive account of scabies—whether sarcoptic, psoroptic or chori- 
optic—on man and other animals as known at that date. It is divided (like 
Gaul) into three parts. Part I deals with classification, anatomy and develop¬ 
ment, and physiology. Part II deals with scabies in man, lemur, bear, hyaena, 
fox, dog, lion, cat, wombat, llama, sheep, ox and fowl. Its main theme is 
that carnivorous and omnivorous animals (bear, dog, hyaena, lion, cat, pig) 
are subject to a form of scabies transmissible to man, due to a Sarcoptes 
which is probably identical with man’s; and that herbivorous animals (horse, 
camel, llama, sheep) may have a Sarcoptes and transmit it to man, but that 
they are more subject to psoroptic and chorioptic scabies not so transmissible. 
Part III is medical, and deals with treatment. 
Bourguignon made many experiments in transferring Sarcoptes from one 
animal to another, and in several passages he calls attention to what he 
believes is the peculiar position held by man with regard to these mites. 
Thus on p. 613 of the Traite pratique he says: “Man has the sad privilege 
of being free from the law which regulates all contagion of animals among 
themselves. His skin always offers an asylum suitable for Sarcoptes ; his 
dermal fluids are always to their taste, and there is to-day no doubt that the 
