108 



muscles; benzine has been suggested. Stimulants may be given 

 to carry patients through xmtil the larvae encyst. 



Prophylaxis. — Kill off rats and mice. — Educate public to eat pork 

 only when thoroughly cooked or thoroughly cured. A practical test 

 of cooking is the white color of the meat on being cut; if the cut 

 surface is reddish and serous, the pork is not sufficiently cooked to 

 kill trichinae. 



As a matter of practical experience, the microscopic inspection of 

 pork has not given the protection it is generally supposed to give. 

 Of 6,329 cases with 318 deaths reported for Germany during the years 

 1881-1898, 3,388 cases with 132 deaths are directly attributable to 

 faults in the inspection. This system directly increases the tendency 

 to eat raw pork, gives the public a false sense of security, and does 

 not give practical results commensurate with its expense. 



ACANTHOCEPHAIA— THORN-HEADED WORMS. 

 Genus GIGANTORHYNCHUS Hamann, 1892. 



Generic diagnosis . — Acanthocepkala, Gigantorhynchidse: Large worms with annulate 

 round to flat, tape-like body. Hooks with 2 roots and completely covered with trans- 

 parent chitin. Proboscis sheath a muscular apparatus, without cavity. Central 

 nervous system caudad of equator of proboscis sheath and eccentric. Lemnisci long, 

 cylindrical, with central canal. 



Type species. — Gigantorhynchus echinodiscus (Diesing, 1851). 



The MoniUform Thorn-headed Worm— GIGANTOBHYNCHUS MONILIFOBHIS 



(Bremser, 1819). 



[Figs. 62 to 58.] 



SPEcmc DIAGNOSIS. — Gigantorhynchus (p. 108): Body attenuated anteriorly, with 

 fine transverse striae or rings, or even constrictions which give the appearance o£ a 

 series of beads, except in the caudal fourth of body, which is nearly smooth and 

 cyliiidrical. Proboscis 425 to 450/1 long, 176 to 190// in diameter, armed with feeble, 

 very curved, 26/t long, hooks arranged more or less in quincunx and forming at most 

 15 transverse and about 12 longitudiual rows. Lemnisci more than a centinfeter in 

 length, cylindrical, undulated posteriorly. 



Male: Length 4 to 4.5 centimeters long; bursa campaniform. 



Female: Length 7 to 8 centimeters (to 27 centimeters after Westrumb). 



Eggs: Ellipsoidal, 85 by 45/(; external envelope thin, yellowish; middle envelope 

 very thick, colorless, homogeneous; inner envelope less thick, colorless, and quite 

 pliant. Embryo striated transversely in posterior two-thirds, and covered with 

 spines which increase in size toward anterior end of embryo, the anterior spines being 

 transformed into booklets with prong and base. 



Development: With beetles {Blaps mucronata) as intermediate host 



Habitat. — Small intestine of various small mammals; brown ra,t{Musdeewmanm); 

 white rat {Mus norvegicus alhus); M. fuscirostris; hamster (Cricetus frumentaritis); 

 dormice {Myoxus querdnus or glis); field mole {Arvicola arvalis or agrestrisf); Lemnus 

 arvalis; and Mustela putorius. It can also develop in man, as has been shown experi- 

 mentally by Grassi and Calandruccio (1888, 521-525). 



Medical significance. — Grassi and Calandruccio report a doubt- 

 ful case of infection in a girl near Catania. Calandruccio infected 



