INJECTION. 



[ 349 ] 



INJECTION. 



Fam. 6. Thecamonadina. Tegument not contractile {Cryptomonadina and some 



AstasicB, Ehr.). 

 Fam. 7. EuGLENiA. Tegument contractile (Astasicea, pt. Ehrenb.). 

 Fam. 8. Peridin^a. Tegument not contractile, a furrow occupied by vibratile cilia. 



Sect. 3. Furnished with cilia, no contractile tegument. Swimming. 



* Naked. 



Fam. 9. Enchelia. No mouth ; cilia scattered without order (not Enchelia, Ehr.). 

 Fam. 10. Trichodina. Mouth visible or indicated by an oblique row, or oral ring of 



cilia ; no cirrhi. 

 Fam. 11. Keronia. Mouth present; an oblique row of cilia, with cirrhi or stouter 



cilia in the form of styles or hooks. 

 ** With a carapace. 

 Fam. 12. Pl^sconina. Carapace diffluent, or decomposable like the rest of the body. 

 Fam. 13. Ervilina. Carapace true, persistent. A short pedicle. 



Sect. 4. Cihated; furnished with a lax, reticular, contractile tegument, or the presence of a 

 tegument indicated by the regular serial arrangement of the cilia. 



* Always free. 



Fam. 14. Leucophryina. No mouth. 



Fam. 15. Paramecia. With a mouth, no oral fringe of cilia. 



Fam. 16. Bursarina. A mouth and an oral fringe of cilia. 



** Fixed, either voluntarily, or by their organs. 

 Fam. 17- Urceolarina. Fixed voluntarily. 

 . Fam. 18. Vorticellina. Fixed, at least temporarily, by their organs or by some part 

 of the body. 



Symmetrical Infusoria. 



* Several types having no relation with each other. 



Gen. : Planariola. Coleps. Chcetonotus — Ichthydium. 



BiBL. Miiller, Animalcula infusoria, 1 786; 

 Ehrenberg, Die Infusion sthierchen als vol- 

 kommen Organismen; id. Abhatidl.undBericht 

 d. Berl. Akad. passim ; id. Ueber d. Geolog. 

 d. unsichtbar. kleinen Lebens ; id. Ueb. d. 

 Formbestandigkeit, ^'C, organisch. Formen ; 

 Dujardin, Hist. nat. d. Zoophytes ; Pineau, 

 Ann. d. Sc. nat., Zool. 3rd ser. iii. v. ix. ; 

 Stein, Wiegtnann's Archiv, 1849; id. Sie- 

 bold und Kolliker's Zeitschr. iii. ; Die Infu- 

 sionsthiere, 1jQv^%\c, 1854; Peltier, L'Institut, 

 1836 ; Focke, Isis, 1836, and Physiolog. 

 Studien ; Kutorga, Naturgeschicht. d. In- 

 fusionsth. ; Meyen, Miiller' s Archiv, 1839 ; 

 Pritchard, History of Infusorial Animalcules; 

 R. Jones, Ann. Nat. Hist. \S39. iii.; Werneck, 

 Ber. d. Berl. Akad. 1841 ; Erdl, Muller's 

 Archiv, 1841; Griffith, Ann. Nat. Hist. 1843. 

 xii. ; Siebold, Lehrb. d. Vergleich. Anat. ; 

 Cohn, Siebold und Kolliker's Zeitschr. iii. 

 260: Kolliker, Sieb. und Kolliker's Zeitschr. 

 i. 198 ; Claparede, Wiegmann's Archiv, Dec. 

 1854, transl. Ann. Nat. Hist. 2 ser. xv. 

 p. 211 ; Schneider, ibid, p. 191, transl. ibid, 

 xiv. p. 322. 



INJECTION. — The art of filling the 

 vessels and other minute tubular organs of 



animals with coloured substances, by which 

 their relative size, arrangement, and relation 

 to the surrounding parts may be made ma- 

 nifest. The substances used for injections 

 consist of powders, mostly insoluble, mixed 

 with some liquid which holds them in sus- 

 pension or solution ; and while in this state 

 they are driven into the vessels by a syringe 

 or some similar contrivance. We shall first 

 give a sketch of the apparatus requisite, and 

 the method of making the liquids for inject- 

 ing the tissues of the Vertebrata, before 

 treating of the process itself. 



Syringe. Two or three syringes are requi- 

 site, of various sizes, adapted to the volume 

 of injection to be thrown into the vessels, or 

 the size of the animal or part to be injected. 

 In most cases, one holding 6 drms. or 1 oz., 

 and another holding about 2 oz. will be 

 found most generally useful. Each syringe 

 must be provided with two rings at the 

 upper part next the handle, so that it may 

 be firmly and easily held. The syringes 

 when in use should be siu-rounded by a roll or 

 two of flannel fastened with string, to prevent 

 their rapid coohng, and the flannel should 

 be kept as dry as possible during the process. 



