168 PHRACTOCEPHALUS. 



of mail, consisting of strong plates, connected by- 

 cartilage, and moveable, like so many joints." 



Among the few specimens of this form which 

 have been dissected, the stomach has been seen to 

 be large and round ; in the D. costatus of Yalenc. 

 giving off at its base, on the right side, a branch 

 which is prolonged to a duodenum nearly equal in 

 size, which performs many folds beyond the stomach. 

 The spleen is flat and large ; the liver displays only 

 a small lobe, and the gall-bladder is oval, with the 

 kidneys large ; the swimming-bladder large ; the 

 fibrous coat thick, and witliin, as if it were laid in 

 folds. There is room for much research regarding 

 their whole structure, and particularly for the correct 

 study of their habits and manner of spawning, the 

 structure of their respiratory organs, and the nature 

 of the liquid which our author notices having ob- 

 served in the cavity of the skull of only two species. 



These will conclude the descriptions of the spe- 

 cies of the Collection which will enter among the 

 Loricarince ; of the other forms of the Siluridte, no 

 specimens accompany the drawings, and there is 

 thus a difficulty of judging of the value of some of 

 the families which have been lately proposed. We 

 shall, however, continue the genera as naturally as 

 possible, and shall first take some of the more 

 strongly armed or mailed. The genus 



PHRACTOCEPHALUS, Agas. 



is of a depressed form, a head large and dispropor- 

 tioned to the size of the body, strongly mailed, and 



