590 
MR. HUXLEY ON THE ANATOMY OF SALPA AND FYROSOMA. 
of multiplication of the Salpce, but the nature and existence of the sexual organs 
remained undetermined until Krohn and Steenstrup in 1846 discovered the male 
organs ; subsequently Krohn made out the true ovaries also. 
Finally, a most accurate account (to which indeed the present memoir can be 
considered only as confirmatory independent testimony) of the whole course of de- 
velopment and reproduction of the Salpce was given by Krohn in the Annales des 
Sciences for 1846. 
71. Without undertaking the somewhat unprofitable task of giving a detailed 
historical account of all that has been written upon the Salpce, it may be of interest 
to notice, with a view to reconcile, a few of the more important discrepancies among 
the statements of the chief investigators. And first : 
Of the sides and ends of the Salpce. — On so simple a matter as this, almost every 
writer has different views. Cuvier calls the ganglionic surface ventral, the opposite 
dorsal, the nuclear end anterior, the opposite posterior. Savigny appears to follow 
him. Chamisso follows Cuvier as to the anterior and posterior ends, but reverses 
the dorsal and ventral sides. 
MM. Quoy and Gaimard give the ganglionic end as anterior, the nuclear as poste- 
rior, the nuclear side as ventral, the ganglionic as dorsal. 
Meyen gives the same determination. Eschricht considers the nuclear end to be 
posterior, the ganglion side ventral ; as also Sars. 
M. Milne-Edwards seems to follow Chamisso. It is much to be wished that 
some uniform nomenclature could be adopted. The reasons for the terms used in the 
present paper have already been given (5.). 
72. The Nervous System . — The nervous system was denied by Cuvier altogether. 
Savigny describes the ganglion, without recognizing its true nature, as the “ tubercule 
qui dans les Ascidies est contigu au gros ganglion.” 
Chamisso describes what appears to be the thickened edge of the “ ciliated fossa,” 
and states that Eschscholtz considered it to be a nerve {pp. cit. p. 5). 
Quoy and Gaimard describe the ganglion, but omit all mention of the auditory 
sac. 
Meyen claims the discovery of the true nervous system ; but although he figures 
it pretty accurately, he omits all mention of the otolithic sac, and seems after all in 
doubt whether it may not be a respiratory organ ; and it was reserved for M. Milne- 
Edwards to give the first satisfactory account of these structures. 
Both Eschricht and Sars subsequently omit to describe the auditory sac. 
clearly expressed, and they do not always seem to have kept so clearly in mind the modest renunciation of any 
claim on the part of the theory to be an explanation of the facts, contained in the last paragraph of the former 
quotation. 
Finally, it must not be forgotten, that though Chamisso was the first promulgator of the “ alternation,” he 
expressly (with a candour impossible to be too much commended) gives the credit of the conception to his 
companionEscuscHOLTz, “ generationis Salparum primus et perspicax fult indagator amicissimus Eschscholtz,” 
p. 9, and again in the preface to the second fasciculus of his observations. 
