In view of Obersteiner's corroboration of Brown-Séquard's results touching the artificial production and subsequent transmission of epilepsy, Weismann accepts the facts, but, in order to save his theory of heredity, he argues that the transmission may be due to a traumatic introduction of "some unknown microbe" which causes the epilepsy in the parent, and, by invading the ova or spermatozoa as the case may be, also produces epilepsy in the offspring. Here, of course, there would be transmission of epilepsy, but it would not be, technically speaking, an hereditary transmission. The case would resemble that of syphilis, where the sexual elements remain unaffected as to their congenital endowments, although they have been made the vehicles for conveying an organic poison to the next generation. Now it would seem that this suggestion is not, on the face of it, a probable one. For "some unknown microbe" it indeed must be, which is always on hand to enter a guinea-pig when certain operations are being performed on certain parts of the nervous system, but yet will never enter when operations of any kind are being effected elsewhere. Moreover, Westphal has produced the epilepsy _without any incision_, by striking the heads of the animals with a hammer[66]. This latter fact, it appears to me, entirely abolishes the intrinsically improbable suggestion touching an unknown--and strangely eclectic--microbe. However, it is but fair to state what Weismann himself has made of this fact. The following is what he says:-- [66] _Loc. cit._ "It is obvious that the presence of microbes can have nothing to do with such an attack, but the shock alone must have caused morphological and functional changes in the centre of the pons and medulla oblongata, identical with those produced by microbes in the other cases.... Various stimuli might cause the nervous centres concerned to develop the convulsive attack which, together with its after-effects, we call epilepsy. In Westphal's case, such a stimulus would be given by a powerful mechanical shock (viz. blows on the head with a hammer); in Brown-Séquard's experiments, by the penetration of microbes[67]." [67] _Essays_, vol. i. p. 315.