356 



THE FRESH-WATER MUSSEL 



LESS. 



Fig. 94. — Dissection of Anodonta, made by removing the mantle- 

 lobe, inner and outer gills, wall of pericardium, and auricle of the left 

 side, and dissecting away the skin, muscles, &c. of the same side down 

 to the level of the enteric canal, kidney, nervous system, &c. Part of 

 the enteric canal is laid open, as also are the kidney {M) and bladder 

 (dl). The connection between the cerebro-pleural (c. */. gn) and 

 visceral {v. ^i) ganglia is indicated by a dotted line. 



a, anus ; a. ad, anterior adductor ; a. ao, anterior aorta ; a. v. ap, 

 auriculo-ventricular aperture ; bl, urinary bladder ; c. pi. gtt, cerebro- 

 pleural ganglion : d. d, duct of digestive gland ; d. gl, digestive gland ; 

 d.p. a, dorsal pallial aperture ; ex. sph, exhalant siphon ; //, foot ; g. ap, 

 genital aperture ; gon, gonad ; gul, gullet ; i. I. j, inter-lamellar junc- 

 tion ; in. sph, inhalant siphon ; int, intestine ; kd, kidney ; vt, mantle ; 

 mtk, mouth ; /. ao, posterior aorta ; /. ad, posterior adductor ■,pc, peri 

 cardium ; pd. gn, pedal ganglion ; r. ap, renal aperture ; r. au, right 

 auricle ; ret, rectum ; r. p. a, reno-pericardial aperture ; st, stomach ; 

 ty, typhlosole ; v, ventricle ; v. gn, visceral ganglion ; w. t, water- 

 tubes ; X, aperture between right and left urinary bladders. 



(From Parker and Haswell's Zoology. ) 



and above the posterior adductor, finally discharging by the 

 anus (a) into the exhalant siphon, or cloaca. The wall of 



