544 



The Museum Gazette 



For 68 young the Mendelian expectation is 51 S and 17 A. 



It will be seen that while the separate litters do not, as 



a rule, agree with the Mendelian expectation, the totals 



exhibit a close agreement ; the reason is obvious. 



(1) (2) (3) (4) (5) (6) 

 An Angora gives off germ-cells A, A, A, A, A, A 



A hybrid „ „ A, S, A, S, A, S 



Should mating occur between the two with a litter of (say) 

 four, the Mendelian expectation will be realised if the germ- 

 cells in columns 1 to 4 meet ; but each germ-cell in the top 

 row has an equal chance of meeting any of those in the 

 bottom row, so that we might have, among other results, the 

 germ-cells in columns 1, 3, 5 and 6 meeting*when the litter 

 would consist of 3 Angoras and 1 short. 



Coloboma in the Petals of Narcissus. — Specimens have 

 been brought to the Haslemere Museum in which malformed 

 flowers of the Stella narcissus show a cleft in the lower 

 part of both corolla and calyx. It is as if a fourth part had 

 been cut out. The edges of the cleft are well rounded. The 

 coloboma extends to the receptacle but does not involve the 

 ovary. There are six stamens, but in one case two on the left 

 side of the cleft are united through the whole length of their 

 filaments. The ovary in this instance had three cells, and 

 was in all respects symmetrical. The outer part of the corolla 

 (calyx) has four sepals instead of five. The condition exactly 

 resembled that which is sometimes seen in the iris of the 

 human eye, and is known as "coloboma." In the eye it is 

 usually directly downwards and results from defective closure 

 of the fissure which is present at an early stage in the forma- 

 tion of the organ. 



Three flowers growing from the same clump of roots show 

 the malformation and are exactly alike, excepting that in two 

 the coloboma is not directly downwards but slightly to one 

 side. A fourth flower in the same clump is perfect. 



