THE PROPAGATION OF THE GOLDFISH 



ot a distant object to be thrown on the retina at all, consequently the 

 condition is one of near sightedness, or of an optical adjustment for very 

 near objects. The conditions of life * * * would in their restricted quarters 

 actually foster the development of near sightedness, and any variation in 

 that direction would actually tend to be preserved. * * * The name 

 telescope fish in allusion to the protruding eye-balls becomes a misnomer, 

 as the form of the eye is distinctly myopic and short-sighted, and not 

 hypermetropic or far-sighted, as required of an optical organ having tele- 

 scopic capacity." The Chinese designation "Dragon-eyes," would better 

 apply to these breeds of goldfishes. 



o 

 < 

 Pi 



Common Goldfish. 



Double-tailed Japanese Goldfish. 



Telescopic-eyed Goldfish. 



No. I - - 



No. z 



All measurements 

 in millimeters. 



Dr. S. Watase, in writing "On the Caudal and Anal Fins of Gold- 

 fishes" states that in his opinion, artificial selection has produced the 

 abnormal forms of all the fins, and that in all goldfishes, irrespective 



of what breed, the tail fin is 

 above all other parts subject 

 to the greatest variation. 



It is found in one of the 

 following states: i, it has three 

 lobes, one median and two 

 lateral; 2, it consists of two 

 separate halves (paired) giving 

 rise to a four-lobed tail (the 

 "Totsuo-wo;") and 3, it is vert- 

 ical and normal. In the first 

 two classes, the lobes are more or less horizontally spread. The simplest 

 transition state from single to double, is seen when the tail, normal in all 

 other respects, has the ventral edge slightly furrowed by a median groove. 



Fig. 57. Diagram of the vertebra and tail-rays of Goldfishes. 

 Single tail of the Common Goldfish. 

 Tripod tail of the Chinese and Japanese Goldfishes, 

 Webbed tail of the Chinese and Japanese Goldfishes. 

 Double tail of the Japanese Fantail Goldfish. 

 Double tail of the Japanese and Chinese Fringetail and Telescope 

 Goldfishes. 



97 



