The Animal Parasites of Man. Max Braun

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СКАЧАТЬ of which was contractile. After the addition of acetic acid one to three nuclei could be distinguished, 8 µ to 15 µ in size. Actual movements were not observed. Taking everything into consideration, the independent nature of these bodies is, to say the least, doubtful, although it cannot be denied that they possess a certain similarity to the marine Amœba fluida, Grüber or Greeff, and to a few other species. (It is likely that cells present in serous exudation were mistaken for amœbæ.)

      Appendix.

      “Rhizopods in Poliomyelitis acuta.”

      In three cases of poliomyelitis acuta which were investigated by Ellermann, the spinal fluid obtained by puncture of the cord contained bodies, from 10 µ to 15 µ in size, which had amœboid movements and exhibited variously shaped pseudopodia in large numbers. After staining, a usually excentric nucleus, about 1·5 µ in size, was demonstrated in them.

      Order. Foraminifera, d’Orbigny.

      The order is divided by Max Schultze into Monothalamia and Polythalamia. Only a few of the former can be considered here.

      Sub-Order. Monothalamia. (Testaceous Amœbæ).

      These forms occur frequently in fresh water, rarely in sea water. They possess a shell which is either pseudo-chitinous in character, or consists of foreign particles, or in a few cases is composed of siliceous lamellæ. There is usually an orifice for the protrusion of pseudopodia. The only representative of the order of interest here is:—

      Genus. Chlamydophrys, Cienkowski, 1876.

      The genus is based on a form which A. Schneider carefully investigated and considered to be the Difflugia enchelys of Ehrenberg. L. Cienkowski rediscovered this same form and created for it the genus Chlamydophrys. We agree with this view, but not with the renaming of the organism (so common at the time). If the parasite in dung, Chlamydophrys stercorea Cienk. is identical with Difflugia enchelys of Ehrenberg, the old specific name should be retained.

      The genus is characterized by the possession of a hyaline, structureless, slightly flexible shell which is ovoid or reniform. At the more pointed pole there is an orifice situated terminally or somewhat laterally, serving for the emergence of the filiform pseudopodia (fig. 13, a). The protoplasm does not entirely fill the interior of the shell. An equatorial zone bearing excretory granules divides the shell internally into two almost equal portions. The anterior portion is rich in vacuoles and serves for the reception of nutriment and for digestion. The posterior part is vitreous, and contains the nucleus. One to three contractile vacuoles are situated in the equatorial zone.

      Chlamydophrys enchelys, Ehrbg.

      Syn.: Chlamydophrys stercorea, L. Cienkowski.

      This species (fig. 13) is found in the fæces of various animals (cattle, rabbits, mice, and lizards), and also in quite fresh human fæces. According to Schaudinn, the parasite occurs so frequently in the human fæces that it must be considered of wide distribution. The species must traverse the intestine of man and animals during one stage of its life cycle, as Schaudinn showed by experiments on himself and on mice. He infected himself with cysts (fig. 14) by swallowing them, and evacuated the first Chlamydophrys as early as the following day. After the evacuation of numerous specimens on one of the following days the infection ceased.

      The nucleus of a living specimen is surrounded by a hyaline, strongly refractile chromidial mass, arranged in the form of a ring. Chromatin stains colour it darkly.

Asexual multiplication (fig. 13, b), which takes place in fæces, follows a similar course to that of allied forms (e.g., Euglypha, Centropyxis). It commences by the cytoplasm issuing from the orifice of the shell and assuming the shape characteristic of the mother organism, but in a reverse position. The nucleus then divides by mitosis, when the daughter nuclei move apart from one another. The chromidial ring also divides into two portions by a process of dumb-bell like constriction. The one daughter nucleus remains in the mother organism, the other moves towards the daughter individual, which then separates from the parent.

      Fig. 13.—Chlamydophrys enchelys. a, free, motile form, showing nucleus, equatorial granules, vacuoles and pseudopodia; b, dividing organism. × 760. (After Cienkowski.)

      In this species plasmogamic union of two or more individuals (up to twenty) is frequently observed. Such colonies may similarly divide, and in this way monstrosities frequently arise. When drying of the fæces, or deficiency of food occurs, encystment takes place apparently spontaneously. The whole body, as stated by Cienkowski, issues from the shell, assumes a spherical shape (probably with discharge of water) and becomes surrounded with a thick membrane (fig. 14). After the addition of water and the escape of the encysted Chlamydophrys, a new shell must be formed. Schaudinn, who has not given a more detailed description of the process of encystment in this species, but refers to Cienkowski and to similar observations made on Centropyxis, states of the latter that the encystment takes place within the shell.

      Fig. 14.—Chlamy­do­phrys en­che­lys, en­cyst­ed; on the left the old cap­sule. × 760. (After Cienkowski.)

The sexual multiplication is accompanied by shedding of all the foreign bodies and of the degenerating nucleus. The protoplasm, now contracting into a sphere, remains behind in the shell with the chromidial mass. From the latter several new nuclei arise (sexual nuclei) often eight in number. The cytoplasmic sphere then segregates into as many spherical portions as there are nuclei present. When they have assumed an oval form, two flagella develop at one pole and the flagellispores swarm out of the shell.35 The biflagellate swarm-spores, or gametes, copulate in pairs and apparently the individuals of the pairs of gametes arise from different mother organisms. The zygote secretes a thick covering which soon becomes brown and rough. These zygote cysts or resistant spores must now pass from the intestine of an animal in order to complete their development. The escape of the cyst contents does not always take place in the intestine; often it does not occur until after defæcation. These shell-less individuals (amœbulæ) soon become invested with a shell. But in the alkaline intestinal contents, shell formation may proceed even while the organism is in the intestine, and multiplication may take place.

      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 СКАЧАТЬ