52 SUMMABY OF OURKENT RESEARCHES RELATING TO 



The followiug forms were examined : — (1) Bhynchohothrium corol- 

 latum, from tlie intestine of Mustelus levis ; (2) Scolices of Tetrarhyn- 

 chus, from the muscles of Orthagoriscus mola (probably T. gracilis) ; 

 (3) Anthocephalus elongatus, from the liver of the same fish ; and (4) 

 Anilioceplialus reptans, from Symnus lichia. 



The scolex may be divided into three parts : (a) a cephalic region, 

 which carries the sucker ; (b) a cervical region, containing the sheaths 

 of the proboscis ; and (c) a bulbous region, which carries the swellings 

 of the proboscis. In the first of these we find in the more anterior 

 sections four outer cephalic and four inner cephalic nerves ; in the 

 succeeding sections these eight nerves are thicker and more distinct, 

 two are now approaching the region of the cerebrum ; in the next 

 section we find on either side a commissure between the upper and 

 lower internal cephalic nerves ; then one between the upper and lower 

 outer nerves ; within these commissures there are small bipolar gang- 

 lionic cells with a large nucleus and a distinct nucleolus. The inner 

 cejihalic nerves give ofl' smaller ramules. 



Further back, not only are the four upper connected by commis- 

 sures with the four lower nerves, but the two inner, on either side, 

 are connected by a transverse band with the two outer. From the 

 outer angles of the squarish mass thus formed a strong nerve is given 

 off which passes to the sucker. As yet, the two halves of the cerebrum 

 appear to be independent ; but, further back, there are two connecting 

 commissures. Still further back sections are found to exhibit a 

 united transverse commissure, which gives rise to a band-shaped 

 cerebral mass, enlarged towards its middle and at either end. 



The author then compares this account of what obtains in T. gracilis 

 with the arrangements which are found in the other forms that he 

 examined. 



Passing to the cervical portion of the scolex, we find the two 

 longitudinal trunks which arise from the brain ; they lie, on either 

 side, within the dermo-muscular tube, between the ascending and 

 descending water-vessel. Here and there they give off delicate nerves 

 which, generally, pass off to the dermo-muscular tube. The author 

 directs attention to tlie presence of a somewhat disturbing element on 

 the inner side of the nerves ; these appear in section as dotted masses ; 

 they turn out to be the united efferent ducts of the large number of 

 gland-cells which are imbedded in the parenchyma of this region of 

 the body. 



In the bulbous portion the longitudinal nerves present much the 

 same arrangement as in the cervical part, and the chief interest centres 

 in the branches which are given oft' from them ; the separate fibres of 

 these enlarge here and there into very long and large ganglion-cells. 

 In the proglottides the lateral nerves extend to the end of the chain, 

 retaining their former relative position ; they are best developed in 

 the more anterior joints, in which the generative organs are still 

 feebly developed. Towards the hinder end they become more in- 

 distinct. 



After some critical remarks on the observations of earlier observers, 

 the author passes to Amphilina, an unjointed Cestode ; the spongy i 



