Parasites : a treatise on the entozoa of man and animals including some account of the ectozoa / by T. Spencer Cobbold.

  • Cobbold, T. Spencer (Thomas Spencer), 1828-1886.
Date:
1879
Catalogue details

Licence: Public Domain Mark

Credit: Parasites : a treatise on the entozoa of man and animals including some account of the ectozoa / by T. Spencer Cobbold. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

    20/528 (page 4)
    I. Fldkes. Tkematoda.—This group embraces several fami- lies of parenchymatous worms. The various species exhibit oue or more suckers^ which the older naturalists regarded as so many mouths or perforations. Hence the ordinal title. The term fluke is of Saxon origin, meaning anything flat. Thus, it has been applied to sole-fish or flounders, to tbe flattened halves of the tail of cetaceans, to the blades of anchors, and so forth. Although the common liver fluke is flat, many species of the order are round, biconvex, or even filiform organisms. I recognise six families :—Monostomidce, BistumidcB, Amphisto- mida, Tristomidce, Polystomida, and Gyrodactylidce. Most of the species are entozoal; but many adhere to the surface of the body of piscine hosts. II. Tapeworms. Cestoda.—This comprises not only the tapeworms, but also the measles and other bladder-worms or cystic Entozoa of the old authors (Cystica). The Greek word liestos means a band or girdle; hence the ordinal term above given. The bladder-worms, including Hydatids, Cysticerci, &c., are the larval stages of growth of various tapeworms. The further reduction of this order into sub-orders or families requires careful attention. At present we have Taniada, Acan- thotceniadcB, Dibothridce {=Bothriocephalid(B), DiphyllohothridcB, Tetrar]'iynchid(S, and Tetraphyllohothridcs. All the genera and species are entozoal. The proposal to separate the snouted or proboscidiform tapeworms {Bhynchotceniada) from those in which the rostellum is absent {Arhynchotceniadee) does not recommend itself to my judgment. III. RoDisTDWOKMS. Nematoda.—This series comprises not only lumbricoid or roundworms proper, but also threadworms. The term derives its origin from the Greek word nema, signify- ing a thread. It likewise includes the strongyles, the term strongulos meaning round or cylindrical. This is a very extensive group whose parasitic members are strictly entozoal, whilst the non-parasitic forms are either entirely free or they infest plants. Some of the so-called free nematoids live in the slime of animals. The artificial classification by Schneider, based on the muscular system, places these parasites in three well-marked groups, but I think it a disadvantage to separate widely many really closely allied forms. Thus, in h\s Polymyarii we have the genus Eustrongylus, and in his Meromyarii the Strougyli proper. Most of the genera may be fairly included in the following families :—Ascaridce, Gheiracanthidce, GucullanidcE,