486 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [384] 
Larval state-—Great numbers of encysted Rhynchobothria were found, 
mostly in capsules, between the mucous and submucous coats of the 
stomach of the Squeteague (Cynoscion regale) and the Bluefish (Poma- 
tomus saltatrix), which appear to be the young form of this species. 
The proboscides and their hooks agree. The bothria and their lobes seem 
to be identical. The sequence from these fishes to the Dusky Shark 
is a natural one, and in the absence of any evidence to the contrary it 
may be fairly assumed that they are the encysted larve of R. bisulcatwmn. 
It is the purpose of the author to publish figures and a fuller descrip- 
tion of these in a subsequent paper. 
Habitat.—Sirobile: Dusky Shark (Carcharias obscurus); pylorus and 
intestine; very abundant. 
Scolex encysted: Squeteague (Cynoscion regule), Bluefish (Pomatomus 
saltatrix); submucous coat of stomach and peritoneum; very abundant. 
Wood’s Holl, Mass., August. 
This worm resembles &. paleaceum Kudolphi and Van Beneden. 
(Dies., Revis. d. Ceph. Ab. Par., p. 294.) 
Tetrarhynchus lingualis Van Beneden (Les Vers Cestoides, p. 151, tab. 
xvii, 4, 6-9). It presents many differences from Van Beneden’s figures 
and descriptions, however, among which may be mentioned here, as of 
most importance, the number and form of the hooks, the articulation of 
the neck with the body, and the position of the male genital openings. 
Van Beneden represents the latter in R. paleaceum as always opening 
at the posterior third of thesegments. In all of the different forms of R. 
bisulcatum they open uniformly near or in front of the anterior third. 
Rhynchobothrium tenuicolle Rudolphi. 
[Plate V, Figs. 17,18.] 
Tetrarhynchus tenuicollis Rud., Synops., 130 and 451. Creplin, Ersch. and 
Grub. Encyel., xxxii, 295, note 34, and Erichson’s Arch., 1846, 149. Du- 
jardin, Hist. Nat. des Helminth., 551. 
Lhynchobothrium tenuicolle Diesing, Sitzungsb., xiii, 1854,595; and Revis. der 
Ceph. Ab. Par., 299. 
Tetrarhynchus corollatus Siebold, Zeitsch. fiir Wissensch. Zodl., ii, 241 (in part). 
The characters given for this species by Diesing are the following: 
Head with suborbiculate lateral bothria, converging at the apex and 
with an elevated border; neck very long, subcylindrical, slender, rounded 
at the base; segments of the body bacilliform, ultimate ones contracted, 
easily failing off. Length of head and neck, 5.5™™ to 6.5™™; length of 
body, 15™™ to 17™™; breadth, 0.56™™. 
The proboscides for the larval condition are described as filiform, very 
slender, and armed with a long series of ternately verticillate and re- 
curved hooks. 
The published descriptions of this species are meager and unaccom. 
panied with figures. It is with some hesitation, therefore, that I refer 
a few Rhynchobothria from the spiral valve of the Smooth Dogfish (Jfus- 
telus canis) to this species. 
