4SO ON APPENDICULARIA FLABELLUjM 



" Anteriorly, a nerve is given off from the ganglion (a) which 

 becomes lost about the parietes of the respiratory aperture ; another 

 large trunk passes backwards (i^) over the left side of the oesophagus, 

 and between the lobes of the stomach, until it reaches the appendage, 

 along the axis of which it runs, giving off filaments in its course, 



fig. 2.- 



" There is no proper branchia ; but that organ seems to be repre- 

 sented by a richly-ciliated band or fold {e) of the inner tunic, which 

 extends from the opening of the mouth forAvards, along the ventral 

 surface of the respiratory cavity, to nearly as far as the ganglion ; 

 when it divides into two branches, one of which passes up on each 

 side, so as to encircle the cavity (_/). This circlet evidently represents 

 the ' ciliated band ' of Salpa. 



" The mouth {g) is wide, and situated at the posterior part of the 

 ventral parietes of the respiratory chamber. The oesophagus (//) 

 short, and slightly curved, opens into a wide stomach (i) curved 

 transversely, so as to present two lobes posteriorly. 



" Between the two lobes, posteriorly, the intestine (Ji) commences, 

 and passing upwards (or forwards) terminates on the dorsal surface 

 just in front of the insertion of the caudal appendage (/). 



" The heart lies behind, between the lobes of the stomach. I saw 

 no corpuscles, and the incessant jerking motion of the attached end 

 of the caudal appendage rendered it very difficult to make quite sure 

 even of the heart's existence.'' 



" The caudal appendage (A) is attached or rather inserted into 

 the body on the dorsal surface just behind the anus. It consists of a 

 long, apparently structureless, transparent, central axis (?«), rounded 

 at the attached, and pointed at the free end. This axis is enveloped 

 in a layer {o) of longitudinal, striped, muscular fibres ; which form the 

 chief substance, in addition to a layer of polygonal epithelium cells, 

 of the broad alary expansion on each side of the axis." 



" The only unequivocal generative organ I found in Appendicularia 

 was a testis (/>), consisting of a mass of cells developed behind and 

 below the stomach, enlarging so much in full-grown specimens as to 

 press this completely out of place. 



" In young specimens the testis is greenish, and contains nothing 

 but small pale circular cells ; but in adults it assumes a deep orange- 

 red colour, caused by the presence of multitudes of spermatozoa, 

 whose development from the circular cells may be readily traced. 



" This orange-red mass, or rather masses, for there are two in 

 juxtaposition, is described by Mertens as the ' Samen-behalter ' or 

 vesiculse seminales. He describes them as making their exit, bodily, 



