STAINING TAIL FIN CHROMOSOMES 



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PENTAPLOrD TETRAPLOID TRIPLOID 



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CHROMOSOMES IN THREE TAILTIPS 



Small portions of the epidermis of a tetrap- 

 lold, a triploid, and a diploid talltip, 

 each with a mitosis in metapliase. Below, 

 the tliree metaphase plates enlarged. Tlie 

 chromosomes catinot be counted accurately in 

 photomicrographs, but the dimensions and the 

 general appearance of the w)iole chromosome 

 group clearly indicate differences in chro- 

 mosome number. The average size of the non- 

 dividing nuclei is also roughly proportional 

 to the number of chromosomes t)iey contain. 



Polyploidy In "Eurycea blsllneata " 

 (From FankJiauser 1959 = 

 Joux. Heredity 30:579) 



RELATIVE SIZES OF NUCLEI AND CELLS FROM 

 THE TAILFINS OF LARVAE OF TRITURUS 

 VIRIDESCENS WITH DIFFERENT NUNfflERS OF 

 CHROMOSOME SETS 



Above: Surface view of nuclei of epider- 

 mis cells. Nuclear size increases ap- 

 proximately in proportion to chromosome 

 number. Below: Nuclei and cell boun- 

 daries of single gland cells (Leydig 

 cells) . Cell size Increases witli nuclear 

 size. 



(From Fankhauaer l°ik'j: 

 Quart. Bev. Biol. 20:20) 



pentaplOid diploid 



Body cavity of pentaploid distended 

 dist&nded with fluid (ascites). In 

 both larvae the melanophores are 

 "expanded". Tracings of photomicro- 

 graphs. 



" TrlturuB virldeacena " 



(From Fankhauaer 19'4-0: 

 Proc. Nat. Acad. Scl. 26:526) 



