Fig. 213.—Cephalic end of Sparganum mansoni, Cobb. (After Leuckart.)
Fig. 214.—Sparganum mansoni: on the right in transverse section. Natural size. (After Ijima and Murata.)
These plerocercoids were discovered in 1882 by P. Manson during the post-mortem on a Chinaman who had died in Amoy, twelve specimens being found beneath the peritoneum and one free in the abdominal cavity. Cobbold described them as Ligula mansoni, and Leuckart, who contemporaneously reported a case in Japan, termed them Bothriocephalus liguloides. Ijima and Murata reported eight further cases, and Miyake records nine further cases, seven of which are recorded in Japanese literature.
The plerocercoid, which hitherto alone is known to us, attains a length of 30 cm. and a breadth of 3 to 6 to 12 mm. The ribbon-shaped body is wrinkled, the lateral borders are often somewhat thickened, so that the transverse section has the form of a biscuit; the anterior end is usually wider and has the head provided with two weak suctorial grooves, either retracted or protracted.
The parasite makes migrations within the body, and thus may reach the urinary passages; then it is either evacuated with the urine or has to be removed from the urethra; not rarely it causes non-inflammatory tumours on various parts of the skin, which are at times painful and at times vary in size.
Nothing is known of its development and origin.
Sparganum proliferum, Ijima, 1905.