. Bulletin of the Southern California Academy of Sciences. Science; Natural history; Natural history. PLATE 38 Arviillifer moniliforinis. Male, x. Although it is similar in general appearance to the female, it presents a form of sexual dimorphism which has escaped the eyes of most observers. Each abdominal ring or segment in the anterior region of the body is provided on the ventro-lateral bor- der with a pair of digitate processes, one on either side, which are directed ventrally and slightly backwards. In addition, there are four other pairs on the cephalothorax. Each process consists o
. Bulletin of the Southern California Academy of Sciences. Science; Natural history; Natural history. PLATE 38 Arviillifer moniliforinis. Male, x. Although it is similar in general appearance to the female, it presents a form of sexual dimorphism which has escaped the eyes of most observers. Each abdominal ring or segment in the anterior region of the body is provided on the ventro-lateral bor- der with a pair of digitate processes, one on either side, which are directed ventrally and slightly backwards. In addition, there are four other pairs on the cephalothorax. Each process consists of a delicate, triangular outgrowth of the cuticle and terminates in a round, sucker-like disk. These structures probably function as claspers and aid the parasite in its movements or help it to ad- here to the surface of some organ within the body cavity of the host. Both Sambon and v. Heymons noted these peculiar pro- cesses but regarded them as sharply-pointed denticles while Miss Hett observed their finger-like shape l)Ut did not mention the sucker pads at their distal ends. The first and second pair of digitate processes are situated just above the outer hooks along the anterior border of the cephalo- thorax. The third and fourth pair project at equal distances on the ventro-lateral edge, at either side of the head and in line with the two rows which represent the abdominal pairs. The latter are more greatly developed forward and decrease in size pos- teriorly until they gradually disappear beyond the sixteenth seg- ment. In female specimens, the first five or six anterior segments are sometimes slightly swollen at the posterior edge of the seg- ments at either side of the ventro-lateral border. The swellings are not as prominent as papillae and may perhaps represent the vestiges of the male digitate processes as they occupy the same relative position. 120. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readabi
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