Schaudinn’s further communication was of special interest; it was to the effect that Chlamydophrys was related to
Leydenia gemmipara, Schaudinn, 1896.
In the fluid removed by puncture from two patients suffering from ascites in the first medical clinic in Berlin, cellular bodies with spontaneous movement were found, which Leyden and Schaudinn regard as distinct organisms. They remained alive without the use of the warm stage for four or five hours, the external temperature being 24° to 25° C. In a quiescent condition they were of a spherical or irregular polygonal form. Their surface was rarely smooth, being beset with protuberances and excrescences (fig. 15). The substance of the body was thickly permeated with light refractile granules with a yellowish shimmer. The hyaline ectoplasm was rarely seen distinctly. All sizes from 3 µ to 36 µ in diameter were observed. The movements were rather sluggish, the ectoplasm in the meantime appearing in the form of one or several lamellæ, in which also strings of the granular endoplasm occurred, and frequently protruded over the border of the hyaline pseudopodia. The tendency for the joining of several individuals by means of their pseudopodia was so marked that associations ensued similar to those known in free-living Rhizopoda.
The cytoplasm enclosed blood corpuscles as well as numerous vacuoles, one of which pulsated slowly about every quarter of an hour. A vesicular nucleus the diameter of which was about equal to one-fifth of the body was present.
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.
Variation in the form of the nuclear apparatus occurs. One nucleus only, which may be compact or vesicular, is known in many species. This nucleus is situated either centrally or sometimes near the flagellar end of the body, but its position is subject to variation. The flagella may arise near the nucleus. Other structures, such as an axial filament and a rhizoplast, may be present. Some flagellates are binucleate, the two nuclei—which often differ in size and shape—being separated from each other. One of these nuclei is the principal, vegetative or trophic nucleus; the other is an accessory nucleus, frequently termed the blepharoplast, flagellar or kinetic nucleus. One or more small basal granules are often present at or very near the origin of the flagella.
Multiplication is by fission, usually longitudinal, which may occur in either the free or encysted forms. Division is initiated by that of the nucleus or nuclei (especially the kinetic nucleus). The basal granule divides also. Collars and chromatophores, if present, likewise separate into two. Variation in the method of doubling the original number of flagella occurs. In most organisms, especially uniflagellate forms, the flagellum splits lengthwise, after division of the basal granule, blepharoplast and nucleus. The daughter flagella may be of the same or different lengths and thicknesses. Other flagellates at division are said to produce new flagella in the neighbourhood of the original ones. The daughter organisms in such cases are provided with one or more parental flagella in addition to newly formed ones. It has been stated that in certain cases the parent flagellate retains all its flagella, while new ones arise ab initio in the cytoplasm of the daughter forms.
Multiplication by longitudinal fission may be interrupted sooner or later by the production of gametes, which form zygotes, from which new generations of individuals arise. In many flagellates gamete formation and sporogony are unknown, and asexual reproduction by fission alone prevails.
Incomplete division results in the formation of colonies of individuals. These colonies must not be confused with the aggregation rosettes of flagellates found among the parasitic Mastigophora. The individuals of aggregation rosettes are capable of immediate separation from the rosette at will.
A number of parasitic Flagellata produce non-flagellate stages which are very resistant to external conditions, the assumption of which forms serves to protect the organisms during their transference from one host to another. Such non-flagellate forms possess one or more nuclei, are usually of an oval or rounded contour, and are capable of developing into the full flagellate on the return of more favourable conditions. These forms are often known as the post-flagellate stage of the organism. When ingested by a new host, the post-flagellate coat becomes more flexible, and the phase of the organism which now recommences growth is known as the pre-flagellate stage; it gradually develops into the typical flagellate organism.
Many Flagellata live free in fresh and salt water. They prefer stagnant water,