502 NICHOLAS ZOGRAFF. 



these fishes develope more mental activity than any other 

 species of the same class ; such instances we see, for example, 

 in their mode of nest building (Macropodus, Trichogaster), 

 their changes of basins (Anabas, Ophiocephalus), and, lastly, 

 in their way of getting food (Toxotes). Whilst communicating 

 their observations on the life of Labyrinthici, travellers have 

 not found it necessary to acquaint us with the anatomy of these 

 fishes. 



I have not found in existing literature any other reports on 

 the inner construction (anatomy) of the Labyrinthici than those 

 published in the important works of Cuvier and Valenciennes, 1 

 and in the work of Wilhelm Peters, 2 describing the gill-apparatus 

 of some of the Labyrinthici. Both these authors took interest 

 in that striking apparatus, which, thanks to its complicated 

 exterior, received the name of " the labyrinthine apparatus." 



It seems Cuvier was the first and probably the only author 

 who examined the labyrinthine apparatus, Peters having been 

 more interested in the relation between that apparatus and 

 the skeleton of the clavicles. Cuvier thought this apparatus 

 to be a complex of very thin bone lamellae or plates, which 

 served, sponge-like, to retain water for the purpose of moisten- 

 ing the gills of the fish when in the open air. These bone 

 lamellae, according to Cuvier, are nothing but projecting parts 

 of the pharyngeal bones ; their surface is covered with a 

 great quantity of thin sanguiferous vessels, which appa- 

 rently receive the blood from the general gill-artery. How- 

 ever, Cuvier says he is not quite convinced of that, having 

 only had for his experiments samples kept in spirit, thus 

 making it difficult to trace such thin vessels as the artery of 

 the labyrinthine apparatus. Cuvier's views as to the construc- 

 tion and physiological importance of the apparatus have found 

 credit in science, and there is not a good manual that does 

 not describe it in the same manner as Cuvier did. As to 



1 'Histoire naturelle des poissons par Cuvier et Valenciennes,' Paris, 1831, 

 vol. vii, p. 328. 



5 Wilh. Peters, " Ueber das Kiemengeriist der Labyrintbfische," ' Miiller's 

 Archiv fur Anatomie und Physiologie,' 1853. 



