483] PSEUDOPHYLLIDEA FROM FISHES— COOPER 195 



the testes from being continuous from proglottis to proglottis, nor the anterior 

 end of the uterus-sac from protruding considerably into the proglottis imme- 

 diately ahead; In the material from Loia maculosa the myoblastic nuclei 

 and protoplasm of the sagittal fibres are almost as prominent as in A .rugosum. 

 There is a weakly-developed series of external longitudinal muscles arranged 

 in relation to the posterior borders of the anterior segments as described 

 above. The musculature of the ordinary form of the scolex is typical. Trans- 

 verse or circular, sagittal or radial, and longitudinal muscles are about equally 

 developed, the latter entering the base of the organ in scattered groups, altho 

 not distinctly fascicled, and extending to the tip. A series of well developed 

 longitudinally arcuate fibres, arranged around the border of the terminal disc 

 is present, quite as described by the writer elsewhere (1914a :92) for Haploboth- 

 rium glohuliforme. In the enlarged scolex from L. maculosa, altho the general 

 arrangement of the musculature is retained, the number of fibres is greatly 

 diminished and the whole ensemble indicative of not a little degeneration. 

 This is emphasized by the fact that in the unenlarged portion of the organ 

 there is to be seen in sections a deposition of material which stains much Uke 

 that described above for the young pseudoscoHces of A. rugosum. This is 

 absent, however, from the enlarged terminal portion. 



In the form from the salmon the chief nerve strands reach a maximum 

 dorsoventral diameter of about 100/x by a transverse diameter of 40/i. They 

 are located at the extreme lateral limits of the medulla, all of the testes coming 

 between them, as pointed out by Liihe (1900a), and pass dorsal to the inner 

 end of the cirrus-sac and consequently to the vagina, as mentioned by Matz 

 (1892:112). In the scolex the chief strands enlarge at the level of the border 

 of the terminal disc to form two ganglia which are united by a small transverse 

 commissure, the whole arrangement being quite comparable to that present 

 in B. cuspidatus. 



Zschokke (1884:25) said that "Les canaux excreteurs sont paralleles et 

 voisin des bords lateraux," while Fraipont (1881:12) described the system 

 as follows: "La vesicule terminale est petite. Le systeme des canaux descen- 

 dants est fort compUque; ils fournissent des branches laterales de volume tres 

 variable; les unes volumineuses, les autres excessivement greles. Les branches 

 forment un reseau a mailles tres inegales. Des canaux tres fins peuvent partir 

 directement des gros troncs. Dans la tete, les canaux descendants forment 

 un reticulum tres complique. Cretaines ramifications tres fines se terminent 

 par des entonnoirs ciHes identiques a ceux du B. punctatus." In mature pro- 

 glottides about six of these descending canals are seen on each surface of the 

 strobila, as stated by Matz, those on the ventral surface, altho of varying size, 

 being constantly the largest. The outermost of these passes ventral to the 

 cirrus-sac, while the corresponding dorsal one is much more median in position. 

 All of the vessels He just within or sometimes among the inner transverse mus- 

 cles but not so much among the vitelhne follicles as Matz found. In the first 

 segments these twelve canals become reduced to three or four, irregularly 

 arranged on each side of the median sagittal plane, of which one or two may 



