TRICHINA. 



[ 650 ] 



TRICHINA. 



Fig. 765. 



rotten wood,, &c., characterized by a stalked or 

 sessile, simple, membranous peridium, which 

 bursts at the summit, whence the densely 

 interwoven free capillitium expands elasti- 

 cally, carrying with it the spores. The ca- 

 pillitium is composed of tubular filaments 

 (elaters), containing spiral-fibrous secondary 

 deposits, like the elaters of Marchantia (PI. 

 32. fig. 39). In some species the elaters bear 

 numerous little spinulose processes. The 

 genus is divisible into two groups. In the 

 first (Hemiarcyria) the dehiscence of the 

 peridium is obscurely circumscissile (fig. 

 765), the capillitium 

 dense ; these are 

 always stalked, usu- 

 ally of reddish co- 

 lour when young. 

 Some species have 

 the peridia fascicu- 

 late on a compound 

 peduncle (fig. 765), 

 others separate. In 

 the other division 

 ( Goniospora), the 

 dehiscence of the 

 peridium is irregu- 

 lar, the capillitium 

 lax, the peduncle 

 short or absent, the 

 colour at first whi- 

 tish, changing to yellow, and the spores rather 

 angular. In T~ Serpula and reticulata the 

 sessile peridia are irregular, flexuous, ser- 

 pentine or annular bodies; in most of the 

 other species the peridia are pyriform, tur- 

 binate, or of some analogous form. The 

 elaters (PL 32. figs. 39 & 40) are interesting 

 objects, and form good tests for the defining 

 power of the microscope under very high 

 powers. They must be mounted in a very 

 thin stratum of liquid. 



BIBL. Berk. Brit. Flor. ii. pt. 2. p. 319, 

 Ann. Nat. Hist. vi. p. 432, ser. 2. v. p. 367; 

 Fries, Syst. Myc. iii. p. 182, Summa Veg. 

 457 ; Greville, Sc. Crypt. Fl. pi. 266, 281; 

 Henfrey, Linnean Traws.xxi. p. 221 ; Currey, 

 Microsc. Journ. iii. p. 15. 



TRICHINA, Owen. A genus of Entozoa, 

 of the order Coelelmintha and family Nema- 

 toidea. 



T. spiralis (PL 16. figs. 16, 17, 18) inhabits 

 the human body, forming opaque white 

 specks, visible to the naked eye, in the vo- 

 luntary muscles. The worms usually exist 

 singly within a cyst situated between the 

 muscular bundles (fig. 16). At each end of 

 the cyst is a group of fat-cells resembling 



u/IqonA 



Trichia rubiformis. 

 Magnified 25 diameters. 



those of ordinary fatty tissues. The cysts 

 are about 1-50'' in length, elliptical or oval, 

 usually narrowed and slightly produced at 

 the obtuse ends, and consist of numerous 

 structureless laminae, in which are frequently 

 imbedded minute granules, consisting of 

 fatty or calcareous matter. The worm is 

 cylindrical, narrowed towards the anterior 

 end, the posterior end being obtuse and 

 rounded. The integument is transversely 

 striated or annular, and exhibits an anterior 

 and a posterior longitudinal muscular band. 

 The mouth (fig. 17 a) is situated at the an- 

 terior extremity, from which a small papilla 

 is sometimes protruded. The first part of 

 the alimentary canal is very narrow, and 

 leads to a broader sacculated portion ; this 

 behind the commencement of the posterior 

 half of the body terminates in a funnel- 

 shaped expansion (fig. 18 c), the remainder 

 of the canal being narrow and lined with 

 pavement-epithelium (fig. 18 d). The man- 

 ner in which the posterior end of the alimen- 

 tary canal terminates is doubtful, whether 

 directly continuous with the anal orifice, or 

 free in the abdominal cavity. M. Luschka 

 describes three valves as existing at the pos- 

 terior end of the body. At the commence- 

 ment of the funnel-shaped portion of the 

 alimentary canal (fig. 16 b) are two rounded 

 glandular sacs. The reproductive organs 

 are not well known. Just below the funnel- 

 shaped portion of the alimentary canal is the 

 csecal origin of a tubular sac (figs. 17 & 18 c), 

 containing a dark granular-looking body 

 (fig. \7 d; fig. 18 e) near its commencement; 

 this extends to the posterior end of the 

 worm, where it either terminates in the anus 

 or in the abdominal cavity. Luschka re- 

 gards this as the male organ, and the dark- 

 looking body as the testis ; but no sperma- 

 tozoa have been detected. 



Some of the cysts and worms are found in 

 a state of fatty degeneration, with granules 

 or globules of fat, and calcareous matter. 



It appears that the Trichina is derived 

 from the food; for M. Herbst found the 

 muscles of two dogs, which had been fed 

 upon parts of a badger containing the worms, 

 to be loaded with them. 



Three or four other doubtful species have 

 been described. 



BIBL. Owen, Trans. ofZool Soc. i. 315; 

 Luschka, Siebold fy Kolliker's Zeitschr. iii. 

 69 ; Bristowe and Rainey, Trans. Path. Soc. 

 v. 274 ; Dujardin, Hist. nat. d. Helminthes, 

 293 ; Herbst, Ann. des Sc. nat. ser. 3. xvii. 

 Kobelt, Valentin's Repertorium, 1841. 



