The pernicious symptoms seldom occur at the beginning of the malaria -Laveran observed no such case among all his rich material; on the contrary, they usually appear only after the intermittent or continued fever has lasted some time, though in any case they may break in very unexpectedly.

Especially in old people does it frequently happen that the disease, after progressing under apparently mild general symptoms and slight fever, suddenly manifests pernicious symptoms (most commonly coma) that are rapidly fatal. In these cases the blood examination is of great prognostic value.

A fever with pernicious symptoms may sometimes recover spontaneously. There are especially numerous cases of repeated hemi plegic, aphasic, hemoglobinuric, a less number of comatose attacks known, which recovered without treatment. Still these are always exceptions and do not relieve the physician from the duty of beginning specific treatment at once, and ordering a change of climate if a severe infection with malignant parasites is confirmed or threatening symptoms are present.

In the following we give a description of the more frequently observed types of pernicious cases, once more insisting that we employ the expression "pernicious" not in the sense of dangerous to life, but in the broader sense of general seriousness.*

* Torti divided the pernicious fevers in the following way: " Quod si lubeat melioris ordinis gratia hasce varias perniciosarum febrium differentias ad terminos scholarum, et ad peculiarem Categoriam reducere, in promptu erit, suppnsita generali intermittentium omnium turn simplicium, turn duplicium, turn triplicium divisione in Benignas et Malignas, istas item subdividere in Comitatas ferali aliquo ' symptomate verum morbum simulante, immo et aequante, adhuc tamen inter mittentes, et in Solitarias, seu nullo peculiari symptomate, sed potius multiplici, et vario comitatas, et ex dispositione intima in continuitatem, atque, et vocant, acutiem quammaxime proclives. Comitatas adhuc intermittentes rursus subdivide mus habito respectu ad conjunctum symptoma, in Colliquativas et Coagulativas, ut continuarum etiam malignarum mos est. Ad Colliquativas erunt referenda? quatour priores species enumerate, quas mutuato nomine ab ipso symptomate vocabimus: I. Cholericam vel Dysentericam; II. Subcruentam vel Atrabilarem; III. Cardiacam; IV. Diaphoreticam. ... ad easdem vero Coagulativas re vocabimus tres posteriores species, videlicet: I. Syncopalem; II. Algidam; II, Lethargicam. Et sic primum membru propositi divisionis explebimus. Quo ad