Heredity of Coat Characters in Guinea-Pigs and Rabbits (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1905 Excerpt: ...on the Mendelian hypothesis. Thus, an examination of Table G shows that only 8 albinos have been produced in a total of 54 young, where 13.5 are expected. Nevertheless, this may be only a chance deviation from the expected proportion of albinos which will disappear as larger numbers are produced. Tables H and I indicate that the hybrid males employed in the matings enumerated in Table G really produce a full quota of albino gametes, and that these are entirely fertile when they meet gametes transmitting black, either active or latent. It is a question of much interest, theoretical as well as practical, whether animals of a particular type, when produced by cross-breeding, form the same sort of gametes as are produced by pure-bred animals of the same type. In the case of albinos this evidently is not always true. From an albino which forms gametes all of which transmit latent black, there may be produced, as we have seen, by crossbreeding with a red animal and then interbreeding the hybrids, albinos of three different sorts as regards the transmission of. latent black pigment. Again, the character of a red race which breeds true may be modified by cross-breeding with black, resulting in the production of yellow young. Thus two red animals, young of black (red reces'sive) red A? red? 2007 red A 2004 red 9 2036 bl. 52013 red A 2054 red p? red 2007 red 9 1307 bl.(red recessive) A 1180 red 2 2027--l "1 1 red?3096 red A 3082 3 yellow young F1g. 11.--A genealogical table showing how cross-breeding between red and black may cause variation in the intensity of the red. 11so, by two different pure-bred red females, when mated together, produced a litter of 3 yellow young. The relationships involved will perhaps be more readily understood from the above diagram (...