HISTORY AND ANATOMY OF THE GOL DFISH 



The nervous system of the goldfish is well developed but of some- 

 what inferior type. The brain is small and appears to consist mainly of 

 ganglia devoted to the special senses. The eyes are large, brilliant and 

 well developed, devoid of eyelids, and have a considerable range of vision, 

 and probably some magnifying power as compared with the human sight. 

 The interorbital space is wide, the eyes being placed at the sides of the 

 head, directed somewhat forward, the angles of vision being both to the 

 front and to the sides. The pupils are nearly round with flattened, slight- 

 ly convex cornea, and are enveloped in a layer of gelatinous substance 

 which covers the cavity of the orbit and permits of considerable move- 

 ment of the bulbus. They have briUiant dark centres and white, yel- 

 lowish or reddish borders. 



Goldfishes are voiceless, having no lungs nor any of the auditory 

 organs present in some species of fishes. 



The nose has two erect nasal appendages below the infraorbital space 

 with tubes leading to sacs lined with a folded olfactory membrane. 

 Anteriorly the water is admitted into the sacs, but posteriorly they are 

 closed and do not connect with the pharynx ; the sense of smell apparently 

 not being very acute. 



The sense of taste is located in the sensory nerves of the palate, in a 

 thick cushion of soft contractile substance supplied with nerves. 



The essential portions of the organs of hearing are present but not 

 fully developed, and consist of rudimentary organs located at the base of 

 the cranial cavity, a labyrinth with vestibule and semicircular canals, but 

 the tympanum and the external parts are entirely absent, though the 

 bones in the temporal region are thin and may partially serve the purpose 

 of conducting soundwaves. 



The sense of touch is very well developed and it would appear that 

 sensations of sound are communicated by vibrations in the water, which 

 act on the sensory nerves of the scales, more especially those of the, lateral 

 line. On this account the fish probably feels, rather than hears, sounds. 



The nerves on the surface of the fish, both of the scales and of the 

 fins, are well developed. 



The fish has a well-organized muscular system in all parts of the 

 body. There are sets of muscles that cover the sides of the trunk, the 

 back, and the tail, composed of many tendons branching from the large 

 lateral muscles, these being divided into dorsal and ventral halves. Each 

 fin possesses a separate system of muscles which governs every move- 

 ment. Internally, the muscles are greatly ramified and control all the 

 organs . 



