. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. ell;obiopsidae 299 partially dividing the left part of the organ of fixation from the larger right part. Now from this left part the large roots take their origin (cf. also Fig. 7/?), and the whole configuration of this part of the organ of fixation presents a striking similarity to that found in (cf. Fig. gb). In the organ of fixation has a rather thick cuticle (necessary to ensure a solid fixation of the parasite in its host); part of this cuticle is pierced by a system of hole
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. ell;obiopsidae 299 partially dividing the left part of the organ of fixation from the larger right part. Now from this left part the large roots take their origin (cf. also Fig. 7/?), and the whole configuration of this part of the organ of fixation presents a striking similarity to that found in (cf. Fig. gb). In the organ of fixation has a rather thick cuticle (necessary to ensure a solid fixation of the parasite in its host); part of this cuticle is pierced by a system of holes so that a sieve plate is formed through which protoplasmatic excrescences (the roots) can protrude. In the proximal parts of these roots may also develop a cuticle, as in the specimen of Fig. gb. The external part of does not show more than about fifty trophomeres, so that the parasite is securely fixed to its host by means of the simple globular or oval organ of fixation. In A. umbellatiis, however, which may have 750-1500 trophomeres, this enormous mass of external organs necessitates the strengthening of the organ of fixation into an immovable organ of anchorage. Originally m the specimen of A. iimbellatus described here the organ of fixation may have had a shape quite similar to. Fig. 9a. Amallocystis umbellatus , type specimen. Section preceding the one of Fig. 8/;. Organ of fixation with sieve plate. /, organ of fixation ;/•, root, x 163. Fig. 96. Amallocystis fagei Boschma, type specimen. Section of lower part of organ of fixation. /, organ of fixation; p, proto- plasmatic excrescences; s, sieve plate, x 283. that found in It must have had a strong cuticle, but the part of the organ of fixation to the left of the sieve plate in Fig. 9^ probably had a thin cuticle, so that the protoplasmatic excrescences (the roots) might absorb food from the host. Gradually the root system became more divided and more strongly developed; at the same time
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