pigmented body looking like an ordinary large intracorpuscular pigmented parasite (Plate I., Fig. 1, i) that has escaped from the red corpuscle in which it had developed. It may be recognized sometimes by the very active movement of the hæmozoin granules. This phase, rarely seen, occurs almost exclusively during the pyrexial stage of the cycle. Further, the quartan parasite does not, as does that next to be described the tertian parasite cause marked enlargement of the blood corpuscle in which it lies; on the contrary, the including corpuscle has often a shrunken appearance with hæmoglobin darker than normal. When mature it completely fills the normal-sized corpuscle, scarcely a rim of hæmoglobin being visible (Fig. 20, f); so that it sometimes looks at this stage as if it were a free and independent body floating about in the liquor sanguinis.*[1] All quartan parasites do not proceed to segmentation, or to gamete formation; some are said to degenerate into the peculiar clear, dropsical-looking spheres, filled with dancing particles (Plate I., Fig. 1, i), which form a striking feature in certain malarial bloods. A considerable proportion of these free, dropsical-looking bodies, with active hæmozoin, are probably male gametocytes which, after being placed on the micro- scope slide, and after escaping from corpuscles, have failed to project their microgamete filaments; others, doubtless, are granular female gametes. The failure to project microgametes, in many instances, is probably not normal, but an effect of mechanical dis- turbance from pressure of the cover-glass, or of other circumstances inherent to the artificial conditions under which we necessarily observe these bodies. In more normal conditions the emission of microgametes may be more frequently effected.
The "daisy"—— as it is sometimes called or segmented phase of the quartan parasite, is more frequently seen in the peripheral blood than is the corresponding phase of the other malarial parasites.
- ↑ * In malarial blood the corpuscles are apt to vary in size, as in other anǣmic conditions. A quartan parasite in a megalocyte may therefore simulate a tertian. Usually the including blood corpuscle is, or seems, smaller than normal.
