700 CLASS XI. 



[Sp. Doliolum denticulatum QUOT and GAIM. The openings of the branchial 

 cavity are short tubes, the anterior denticulate, the posterior surrounded by 

 fine filaments. S. Pacific. If it be ever aggregated, it has not been met 

 with in this state. HUXLEY On Doliolum and Appendicularia, Phil. Trans. 

 1852, pp. 599, 603.] 



\Appendicularia CHAMISSO, QUOY and GAIM. (Oikopleura MERTENS). 

 Body irregularly ovate, with a long appendage attached to the 

 dorsal surface at the posterior part, and making a large angle with 

 the axis of body. Opening into the respiratory cavity anterior, 

 outlets two short tubes ciliated where they leave the cavity, open- 

 ing immediately on the dorsal surface in front of the base of 

 appendage 1 . No proper branchiae. 



There has been much doubt respecting the place and the nature of 

 Appendicularia. CHAMISSO, who found his species in the N. Pacific, con- 

 sidered it to be a Medusa allied to genus Cesium. ESCHSCHOLTZ, who 

 observed the same, or a nearly allied species, in the South Sea, referred it 

 to the Heteropod Molluscs, whilst MERTENS, who voyaged in the same 

 seas, thought it was a Pteropod related to Clio. See CHAMISSO Nov. Act. 

 Acad. Cess. Leopol. Car. x. Pt. 2, p. 362, ESCHSCHOLTZ in OKEN'S Isis, 

 1825, s. 736, MERTENS Mem. de I' Acad. imp. de St. Petersburg, 1831, 

 Tom. i. p. 205. LEUCKART (Zoolog. Untersuch. n. 1854, pp. 80, 81) 

 regards Appendicularia as a larval state of some Ascidian, all of which have 

 an appendage in the early condition, whilst with HUXLEY (On Appendicu- 

 laria and Doliolum, Phil. Trans. 1851, p. 595) and GEGENBAUER (SIEBOLD 

 and KOLLIKER'S Zeitsch. f. wissenscli. Zool. B. vi. 1855, p. 406, &c.) it is an 

 adult form. 



Sp. Appendicularia fldbellum CHAMISSO, see HUXLEY 1. cit., who found the 

 testis in the fully developed condition abounding with spermatozoa: the 

 ovary has not been ascertained ; coast of Scotland, and common in the 

 Bristol Channel near Tenby. For a description of four Mediterranean 

 species, with the anatomy, see GEGENBAUER loc. cit.] 



Anchinia ESCHSCH., RATHKE. Small Salpce aggregated in a single row 

 by a gelatinous filament. See WIEGMANN'S Archiv, 1835, i. p. 58. 



1 [These tubes were first discovered by GEGENBAUER, but from the great transpa- 

 rency, he did not detect their openings on the surface of the animals, but supposed them 

 to conduct the fluid from the respiratory cavity, in order either to mix it directly with the 

 blood, or by expanding more largely to bring it in near contact with the blood through 

 their thin walls. See his paper, pp. 415, 416. HUXLEY, as well by direct observation 

 as by feeding his animals on indigo, saw clearly the external apertures of the tubes in 

 front, and on each side of the anus. In one observation he found the current to set in 

 at these apertures, and out at the anterior opening of the respiratory sac. See his 

 paper on Appendicularia flabellum, Quarterly Journal of Micros. Sc. No. 15, 1856, 

 pp. 181 191.] 



