736 DESCRIPTION OF BOTHRIOCEPHALUS CORDATUS. 



though its peculiarities do not appear to me sufficient to justify his 

 opinion. His description was based on two specimens one without 

 a head, which was found in a man forty years old, from the Depart- 

 ment of Haute Saone, while the other with the head was obtained from 

 a child five years old in Paris. * The former measured 92 cm. in length, 

 but was apparently much contracted, as might be inferred, not only from 

 the segmentation, which extended close up to the head, but also from 

 the form of the proglottides, which possessed considerable thickness, 

 but were never more than 1'5 mm. in length, and had their posterior 

 borders much protruded, so as to embrace in an almost cuff-like fashion 

 the succeeding joints. At a distance of about 20 cm. from the head, 

 the breadth of the chain increases abruptly from about 1 to 4 mm., and 

 then gradually to 9 mm. The head, which suggested the name " crista- 

 tus," is said to be especially characteristic of this form. It is of con- 

 siderable size (3 mm. long, 1 mm. broad, 0*6 mm. thick), and in shape 

 resembles a grain of linseed with the point turned forwards. There are 

 no proper suctorial grooves, but according to the description, the two 

 surfaces of the head are each provided with a projecting ridge, which 

 extends from the anterior apex, and is divided by a furrow into two 

 longitudinal lips. These lips diverge posteriorly, and enclose a groove 

 resembling the calamus scriptorius in the brain. The margins of the 

 ridges are covered with small papillae, and the rest of the head is 

 marked by transverse wrinkles. Characteristic of this form are the 

 numerous calcareous bodies, which penetrate the parenchyma of the 

 head in four longitudinal strands, and extend in such abundance 

 through the neck into the body that Davaine refers, its thickness and 

 stiffness to these deposits. The total length is said not to be more 

 than 3 metres. The ova resemble those of Bothriocephalus latus. 



Bothriocephalus cordatus, Leuckart. 



Leuckart, " Die menschlichen Parasiten," first edition, Bd. i., p. 437 et teq., 1863. 



In the structure of its joints, this form is not unlike Bothriocephalus 

 latus, but on closer inspection cannot be confused with it, not only because 

 of its considerably smaller size and more compressed form, but especially 071 

 account of the structure of the head and anterior end of the body. Un- 

 like the extended, oval, or club-shaped head of Bothriocephalus latus, the 

 head of this form is short, broad, and cordiform, with lateral borders, which 



1 Davaine supposes, it is true, that his B. cristatus is of much more frequent occur- 

 rence. He refers to a report of Cobbold, according to which several worms preserved in 

 the Westminster Hospital Medical School belong to his species, and also to an anonymous 

 Memoir published in 1776 in Kempten, in which his worm is said to be figured in a 

 thoroughly satisfactory fashion. 



