298 REPORTS ON THE STATE OF SCIENCE. 



I was occupied in investigating the caudal fin of Teleostean fishes. I 

 obtained about ninety species of fish in all, the majority of which were 

 supplied in plenty. It is my intention to work out the whole of the 

 collection as soon as possible in Birmingham. I fully anticipate that the 

 results of the work will be of considerable value in this particular branch 

 of study. 



Report of Mr. C. C. Dobell. 



I have occupied the British Association table for four months this 

 year — from March to June. During this time I have been chiefly engaged 

 in studying the life-history of the Sporozoan parasites, which live alter- 

 nately in Cephalopods and Crabs. (The parasites are those now usually 

 known under the name of Aggregata.) In addition to studying the living 

 animals in both hosts, I have been able to preserve satisfactorily a con- 

 siderable amount of suitable material, so as to be able to further the work 

 after leaving Naples. 



Besides investigating the Sporozoan parasites I have also been able to 

 carry out some i-esearches upon the Infusoria {Chromidina and Opalin- 

 opsis) in the liver and kidneys of the cuttle-fish. I have succeeded, 

 I believe, in arriving at a correct interpretation of the chromatin in 

 these forms. 



In addition, I have spent a part of my time in working upon the 

 life-histories of the parasitic protists in Aricia foefida and in Laceria 

 muralis. 



Ex2Jer{men{s in Inheritance. — Interim Report of the Committee, consist- 

 ing of Professor W. A. Herdman (Chairman), Mr. Douglas 

 Laurie (Secretary), Mr. R. C. Punnett, and Dr. H. W. Marrett 

 , Tims. (Dratvn up by the Secretary.) 



On the Inheritance of Yellow Coat Colour in Mice. 



Reasons for this Research. — The primary reason for this research is 

 the unexpected result obtained by Cu^not on cross-breeding yellow mice 

 with mice of other colours. On mating a yellow mouse with one that 

 was grey, black, or chocolate Cu^not always found yellowness to act as 

 a heterozygous Mendelian dominant to the other colour. When yellow 

 F| hybrids so produced were intercrossed they gave an F., generation 

 much in accord with e.xpectation, being composed roughly of three 

 yellows to one recessive. It is the gametic constitution of these extracted 

 yellows which gives cause for surprise, and which is the essential point of 

 importance. Eighty-one of them were tested by breeding, and it was to 

 be expected that of these twenty-seven or so would be homozygous for 

 yellowness, but not even one fulfilled the conditions of Mendelian purity. 

 ' Or, a mon grand etonnement,' says Cuenot, ' je n'en ai pas trouv^ une 

 seule ; les quatre- vingt-un souris etaient toutes egalement het^rozygotes.' ' 



This important and interesting result has attracted explainers of 

 difierent schools. Morgan"'' makes it a text for emphasising his views 

 about 'contamination.' Purity, in the Mendelian sense, he denies, 



' Arch. Zool. Exp. (4), torn, iii., Notes et Revne, p. csyix, 1905, 

 » Science, n.e., vol. xxii. pp. 877-879. 



