306 



pale buff or stone, clouded and blotched with yellowish brown and grey 

 shellmarks, while usually there are also much darker spots, streaks and 

 scrolls of sepia to sienna brown, with indistinct edges. Some varieties 

 are almost white, either without markings, or faintly marked with grey 

 or fine red specks. The well known red variety has a distinctly pale 

 salmon pink ground with reddish brown or pinky red markings. Though 

 rare in England, it is not uncommon in some parts of the Continent and 

 R,ey estimates the proportion of red clutches in Germany at about 6 per 

 cent. Transition stages also occur between the red and brown types. 

 Breeding In Germany the breeding season lasts from the beginning of May to 



Season, j^^j g^^j ^wo broods are often reared. In the S. of England clutches may 

 occasionally be taken in the last days of April, but in the Midlands and 

 northern counties the second half of May is the best time, and on the 

 borders few pairs lay before the first week in June. In the S. of Spain 

 eggs have been taken by the middle of March-. In my opinion only a 

 small proportion of British breeding birds can be double brooded. Full 

 and interesting accounts of the courtship of this species will be found 

 in Howard's BritisJi Warblers, pt. 3, p. 5. Incubation lasts about 15 

 days (Howard); the cock frequently taking part, and both birds sit very closely. 

 Measure- Avcragc of 100 cggs (50 by Rey and 50 by the writer), 19.3x14.56, 



Max. 21.5x15 and 20.6x15.5, Min. 17x13. Abnormal eggs measure, 

 24.2x16, 22.9x15, 14.7x12.1, 12.9x11, etc. Average weight of 14 full 

 eggs, 2.22 g. (R. H. Read); blown eggs average 131 mg. (Rey). 



[In Madeira and the Canaries another subspecies is found, S. atri- 

 capilla heineken Jard. (Eggs figured in Cat. Eggs B. Mus, IV pi. VIII, 

 fig. 10 : Dresser pi. — , fig. 20.) The eggs of this race are laid in April 

 and are subject to extraordinary variation, being frequently boldly mar- 

 ked with reddish brown spots and grey shell marks on a white ground, 

 or finely spotted with blackish and pale violet. The clutch usually con- 

 sits of 3 or 4 eggs: average size of 25 (17 by Koenig and 8 by the 

 writer), 19.06>cl4.17, Max. 21x15 and 20x16: Min. 17x13 and 16x12. 



146. Whitethroat, Sylvia communis Lath. 

 Geographical Races. 



a. European Whitethroat, S. communis communis Lath. 



Plate 27, fig. 6—10 (Germany) 



Eggs: Thienemann, Fortfl. Tab. XX, fig. 6, a.— d. Hewitson. I Ed. I, 

 pi. XLII; II Ed, pi. XXVII, fig. 4: III Ed. pi. XXXV, fig. 1, 2. Baedeker, 



ments. 



In order to avoid discrepancies in nomenclature between the text and plates, 

 the remaining four plates will be issued in later parts of this work. 



F. C. R. J ourdain. 



