452 DR JOHN RENNIE AND MR ALEXANDER REID ON 
tissue in which there is a transverse row of ten or twelve excretory canals (fig. 18). 
These merge in each other, converging to a terminal pore. Longitudinal sections show 
the branches of the canals to be very numerous. 
The body of the cysticercoid consists of a peripheral and a central portion. The 
former is limited by a well-defined, thick cuticle, contains numerous excretory vessels 
(about 60 in transverse section) and a loose parenchyma. ‘The central region contains 
the muscular bulbs of the proboscides, and around these a well-developed mass of. longi- 
tudinal muscles (fig. 16). The, central area at its posterior end merges into the 
protrusible bulb (fig. 17). 
The question of the more exact identification of the species to which the form belongs 
must be left undecided. 
G. R. WaGrner (5) has described a similar form from Phycis mediterranea. 
LITERATURE. 
(1) Artona, V., “ Revisione della famiglia Bothriocephalide s, Str.,” Arch. Parasitol., iii. No. 3, 1900. 
(2) Barro, Proc. Zool. Soc. London, 1853. 
(3) von Linstow, Jahrb. Hamb. Wissensch. Anst., ix. Jahrg., 1891. 
(4) Sutpuey, A. E., National Antarctic Expedition Reports, 1907, ‘‘Cestoda,” vol. iii. 
(5) Wagener, G. R., Verhdlgn. (Nov. Act.) d. K. Leop -Carol. Acad. d. Naturf., Bd. xxiv., Suppl., 
Breslau, 1854. 
(6) ZscHoKKE, Fauna Arctica, ‘ Die Arktischen Cestoden,” Bd. iii., Lieferung i., 1903. 
REFERENCES TO FIGURES. 
c. = cuticula, rm. =retractor muscles of proboscides. 
c.8. = cirrus sac. $.c. = sub-cuticula. 
exc.c. = excretory canals. sh.ov. = shelled ova. 
exc.b. = excretory bulb. t.f. = testes follicles. 
lm. =longitudinal musculature. | ut, = uterus. 
n.c, =nerve cord. v. = vagina. 
0. = ovary. y.c. =yolk cells. 
per.a. = peripheral area, 
EXPLANATION OF PLATES. 
Puate I. 
Fig. 1. Transverse section of Dibothriocephalus scoticus, n. sp., at the level of the ovary. 
Fig. 2. (a) Entire specimen of D. scoticus ; (b) scolex of D. scoticus. 
Fig. 3. (a) Anterior end of Anchistrocephalus microcephalus; (b) immature proglottis ef Anchistro- 
cephalus microcephalus. 
Fig. 4. Four specimens of Dibothriocephalus wilsoni, Shipley. 
Fig. 5, Scolex of Dibothriocephalus coatsi, n. sp. 
Fig. 6. Transverse section of D. coatsi. 
