Multiplication took place by means of division and budding (fig. 15, c), after previous direct division of the nucleus. The buds were supposed to divide repeatedly soon after their appearance, thus giving rise to minute forms of 3 µ.
There was a suspicion in both cases that the ascites was associated with malignant neoplasms in the abdomen, and autopsy confirmed this view in one case.
Fig. 15.—Leydenia gemmipara, Schaud. a, in a quiescent condition, × 1000; b, in the act of moving, × 1000; c, from a fixed preparation, showing a bud, × 1500.
The parasite, which has seldom been observed, has been variously interpreted; for example, it has been regarded merely as altered tissue cells. It is now known, from Schaudinn’s researches, that Leydenia gemmipara is connected with abnormal conditions of Chlamydophrys, occasionally occurring as a commensal in the ascitic fluid. The form is produced when pathological conditions of the large intestine create an alkaline reaction of its whole contents. The formation of shells then often ceases, and these naked Chlamydophrys are enabled to multiply atypically by division and gemmation. Such stages, which are no longer capable of a normal development, are the Leydenia, as Schaudinn has demonstrated.
Class II. MASTIGOPHORA, Diesing.
Sub-Class. FLAGELLATA, Cohn emend. Bütschli.
During the motile part of their life the Flagellata possess one or more flagella which serve for locomotion, and in many cases also for the capture of food. A few groups (Euglenoidinæ, Choanoflagellata) have only one flagellum, others two or several of about equal length (Isomastigoda), or of various lengths (Monadina, Heteromastigoda, Dinoflagellata). The long flagellum is the principal one; the smaller ones on the same organism are accessory flagella. The flagella directed backwards, which occur in the Heteromastigoda and are used for clinging, are termed trailing flagella or tractella. At the base of the flagellum, which is almost always at the anterior end, a Choanoflagellate possesses a cytoplasmic funnel-shaped neck or collar. In the parasitic forms an undulating membrane is often present.
The body of the Flagellata is usually small, generally elongate and of unchangeable form. It is frequently covered by a distinct cuticle, and, in certain groups, by a hard envelope, or it may be more or less loosely enveloped by a gelatinous or membranous covering. An ectoplasmic layer is thin and not always obvious. The granular cytoplasm contains a varying number of vacuoles, one of which may be contractile, and is generally situated near the area from which the flagella arise, that is, at the anterior extremity. The cytoplasm, moreover, contains the nucleus, which is nearly always single; and in many species there are also yellow, brown, or green chromatophores of various shapes, such as occur in plants. Some species feed after the manner of green plants (holophytic), or of plants devoid of chlorophyll (saprophytic); others, again, ingest solid food, and for this purpose usually possess a cytostome; the latter, however, in a few forms is not used for its original function, but is connected with the contractile vacuole. Many parasitic forms feed by endosmosis. A few species possess eye-spots with or without light-refracting bodies.