Observations on the hirudo complanata , and hirudo stagnalis , now formed into a distinct genus under the name, Glossopora

Abstract

The animals named in the title of this paper differ so considerably from the Leech, as to induce the author to remove them from the genus Hirudo, and to form them into a distinct one under the term Glossopora, a term derived from a prominent feature of the animal, namely, its projectile tubular tongue. They resemble the leech, in the body being furnished with a series of rings, in locomotion being effected by the alternate motion of the head and tail, and in the division of one general stomach into several lateral cells or partitions. They differ from the leech in the mouth being furnished with a projectile tubular tongue; in the flat pyriform shape of the body; and in having an abdominal pouch or cavity for the reception of their young. After enumerating the character of the genus. Dr. Johnson expresses his opinion that the Hirudo circulans, Hirudo crenata, Hirudo hyalina , and Hirudo tessulata , will be found to belong to it; and the Hirudo sexoculata , described by Bergmann in the Stockholm Transactions, seems to be the same animal. Its tongue is cartilaginous, flexible, and about one eighth of an inch long. The author describes the Glossopora tuberculata and the Glossopora punctata . The notion that they are capable of reproduction when cut or divided, he considers without foundation. Their food consists chiefly of water Helices; into the shell of which they easily penetrate in consequence of their tapering head, and from the flexibility of the tongue they are enabled to follow their victim to the innermost recess of its habitation. The ova are received into the abdominal pouch of the parent, where they remain till fully evolved, and they are unproductive if moved from this situation.