a 4d 
OE 6 OS OSS OOS FS 9 SP aS PS 9 69 i 9 6 9 6 ns es 
F 
| (The Fertility of the Poecilid Hybrid ! 
& 
el i i 
When three Wisconsin men announced 
that they had produced the now famous 
and much-sought-after hybrid, Platypoe- 
cilus maculatus rubra X Xiphophorus 
helleri, many experienced aquarians 
smiled, talked about Mendel’s law, rever- 
sion to the parental forms, mule fish and 
the like. Many were the terms of good- 
natured derision used by those not for- 
tunate enough to possess them. But now 
it has even been positively proven that 
the hybrid is fertile and breeds true to 
form! ‘Thus far there is no sign of even 
a small fraction of the offspring revert- 
ing. 
For the benefit of new readers of 
Aguatic LIFE, it may not be amiss to 
trace the history of this interesting fish. 
In 1914 the Rev. Paul Wagner Roth, of 
Milwaukee, read in a foreign periodical 
of an attempt to cross Platypoecilus ma- 
culatus rubra with Xiphophorus hellert. 
This he recounted to the members of the 
Milwaukee Aquarium Society. The an- 
nouncement was hailed with considerable 
interest, and experiments were soon be- 
gun. 
inmaiimes rons Nir}. Kev jensent of 
Janesville, Wisconsin, accomplished the 
cross. He described it to the writer as 
follows: “Roth gave me a lot of young 
Helleri and Platys. I kept them in the 
tank here and fed them well on Daphne, 
Corethra larve, etc. I had almost given 
up expecting hybrids. One day I noticed 
a small fish in the tank. I said to myself, 
‘What can it be? I haven’t any fish like 
that.” Then I though of the hybrid. I 
had never seen one, but it proved to be 
‘him’ sure enough.” The triumph was 
announced to the Milwaukee Aquarium 
Society. 
F. R. WEBBER 
LY 6 SOS 9S Ot Pd Ps Ps Psy 
A few months later Mr. Francis H. 
Goodby, also of Milwaukee, announced 
the arrival of about seventy of the new 
fish. About a month later Mr. Jacob 
Merget succeeded in producing them. 
He reports that all of his first batch were 
deformed, the next weaklings, but the 
third physically perfect. Later, Rev. 
Platypoecilus maculatus 
Upper, male of red phase (ruba) Lower, female of black phase (nigra) 
Roth was very successful, so much so 
that the form became popularly known 
as “Roth’s hybrid.’’* 
For a time it was thought by many that 
the hybrids would either be sterile, or else 
would breed back to either parent. About 
a year ago the writer received a letter 
from Mr. Merget, assuring him that he 
had not only produced the hybrids, but 
*An Interesting Fish Hybrid. Rev. Paul 
Wagner Roth. Aquatic Life, Vol. 1, pp. 
55-57, et. seq. Describes hybrid and how pro- 
duced. 
Hybridizing Fishes. Jacob Merget. Aquatic 
Life, Vol. 1, p. 131, et. seq. Describes method 
of accomplishing the cross. 
My “Faulty Techniques.” 
Aquatic Life, Vol. 2, 
fertility of the hybrid. 
Jacob Merget. 
p. 66, et. seq. Records 
