A revision of the adult cestodes of cattle, sheep and allied animals ... / by C.W. Stiles ... and Albert Hassall.
- Charles Wardell Stiles
- Date:
- 1893
Licence: Public Domain Mark
Credit: A revision of the adult cestodes of cattle, sheep and allied animals ... / by C.W. Stiles ... and Albert Hassall. Source: Wellcome Collection.
67/174
![Among the French tapeworms examined not a single head was noticed which could be positively identified as belonging to Th. Giardi. Two ]ieads were found in a bottle containing segments of Th. Giardi and ,1/. expansa, and it is probable that one of these heads belongs to the species now under consideration. Perroncito (3, p. 24(5) describes the scolex of T. aculeata as follows: Testa depressa, quadrangolare, col iato maggiore di millimetri 0.560-0.589, col Iftto minore di millim. 0.250-0.300, lunga millim. 0.500; ventose rivolte in inori, divise da uua depressione, del diametro longitudinals di millim. 0.256-0.264, trasversale di millim. 0.200-0.208. Collo breve r&ppresentato da un restringimento o collaretto del diametro di millim. 0.536. ’ Neumann (13, p. 408) describes the head as “ tetragone ayant un peu plus d’un millimetre de largeur, suivie d’un cou assez long, de largeur moitie moindre que celle de la tete.’1 One of the heads mentioned above agrees very nearly with the description, and is probably the head of Th. Giardi. It was con- nected with a strobila 38mm in length. The head (Plate xn, Fig. 2) is quadrate, stout, 0.506m,n broad, 0.33,nm long (from the anterior extremity to the constriction of the neck). The suckers are very strong, nearly round, with a diameter of 0.192'1. The opening of the suckers in my specimen is elongated. The constriction back of the head measures 0.846u1,n. Segmentation, at first extremely indistinct, begins at this point; 1.6mm distal from this point the seg- mentation is very distinct. The first anlage of the genital organs is noticed about 2.25mm back of the cervical constriction. At first only a small differentiation of tissue is seen in the median line of every seg- ment; this arrangement (Plate xn, Fig. 3) continues for a distance of about 3nn, when it is noticed that the anlage of every segment does not lie exactly in the median line, but slightly to the right or left of it. This diversion from the median line continues, so that 47.5 from the point where it begins the aulagen lie close to the longitudinal (lateral) canals. The oldest segment of this strobila measures 2.5 broad by 0.8'”' long. The genital anlage is very simple, and no traces of testicles can be seen. Thus it is seen that this head and strobila belong to some cestode with alternate genital pores. If it is not a T. Giardi, it must be a new species (or T. Vogti ’t ??). The other head referred to agrees so closely with the head of M. expansa, that it is difficult to believe it can belong to Th. Giardi. Plate xn, Fig. 4, represents seven young segments, each measuring 3.7mmbroad by 0.176mm long. Six of these segments have a single anlage of genital organs, while one of the segments possesses anlagen of two sets of sexual organs, one of which is rather rudimentary. The genital pore has not yet pierced the cuticle of the margin. From about the middle of the lateral margin of each segment two curved and nearly parallel portions of tissue, which color darker than the surrounding paren- chyma, extend across the longitudinal canal into the median field. The](https://iiif.wellcomecollection.org/image/b28122604_0067.jp2/full/800%2C/0/default.jpg)
