Notes and Comments
151
Delacour, however, say that Lanius s. schach and Lanius fuscatus are one and the same bird and this recent find supports their view.
R. A. P.
La Touche in a "Handbook of the Birds of Eastern China" p. 186 makes this significant remark. "However, until specimens of L. schach and L. fuscatus are taken from the same nest, the question must remain unsolved." In his Corrigenda and Addenda on p. 481, he writes of L. fuscatus "It is most probable that, as pointed out by Dr. Stresemann, this Shrike is a melanistic form of L. schach.”
We have not seen Dr. Stresemann's paper on the question and therefore are unacquainted with his evidence. If melanism in L. schach behaves as a simple recessive then if a Rufous bird RR, mated with a Dusky bird rr, the first hybrid generation Rr, would all be Rufous. If two such hybrids mated then on the average in every four chicks one would be RR, two Rr and one rr, i.e., one pure Rufous, two hybrid Rufous and one Dusky. It appears that in the case found by Mr. R. A. Pereira both parents were Rr and therefore one in every four of the chicks would be Dusky; one Dusky and two Rufous chicks in the family of three supports this view.
Major Hutson's note on these birds H.K.N. II, p. 221, is worth quoting. "On June 17, 1931, two adult shrikes, one normal and one dusky, were seen together with a couple of youngsters both of which looked normal; on July 13, two young shrikes, one normal and one dusky were seen together with one adult which was normal. If the view of melanism behaving as a simple recessive is correct then in the first of Major Hutson's examples the parents were probably RR and rr and the youngsters Rr, alternatively the parents may have been Rr and rr and the youngsters Rr but in this case one of the two youngsters by the laws of chance should have been rr and therefore dusky. In the second of Major Hutson's examples the adult seen must have been Rr for in no case with an RR parent is it possible to have one rufous and one dusky offspring, the other parent may have been either Rr or rr as in either case the two youngsters, one rufous and one dusky, could have been obtained. If the other parent was Rr then the rufous youngster could have been either RR or Rr; if the other parent was rr then the rufous youngster must have been Rr.-Ed.
NESTING NOTES.
Violet Whistling Thrush, Myophonus c. coeruleus (Scop.) A nest was discovered in a rather unusual situation on June 8. It was situated in a hole in a bank-the half-dome shaped hole left by an old wasps' nest. The bank formed one side of a deep cutting above Tai Hang, and the nest was twelve feet from the bottom of the bank and about three feet from the top of the cutting, which, however, had a slight overhang, and thus gave ample protection and cover. In fact, had the sitting bird not flown out at my approach, leading to a search for the probable nest, it would not have been discovered.
July 1935.
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