176 * LiEIDjE. 



Hydrochelidon fissipes, Baedeker, Eier Eur. Voj. tab. 32. fig. 3 {18-55- 



63) ; Saunders, Ibis, 1871, p. 399. 

 Hydrochelidon nigra, Dresser, Bi'-ds Eur. viii. p. 327 (1876) ; Saunders, 



Cat. Birds B. M. xxv. p. 17 (1896); Sharpe, Hand-l. i. p. 133 



(1899). 



The eggs of the Black Tern vary from a pointed oval form to 

 pyriform. The ground-colour ranges from* pale buff to brownish 

 buff, and this.is heavily blotched and spotted with reddish brown and 

 blackish brown. With few, exceptions, these markings cover quite 

 half the surface of the shell and are often confluent, especially 

 over the broader half. The underlying markings are numerous 

 and of a dull grey colour. Specimens measure from 1'3 to 1"4S in 

 length, and from -9 to 1-05 in breadth. 



3. Goto del Rey, Spain (Lord Lilfort). Saunders Coll. 



4. South Spain. Lord Lilford [P.]. 

 14. Valkenswaard, Holland, 26th May Saebohm Coll. 



{H. Seebohm). 



18. Valkenswaard ( W. Bridges). Saunders Ooll. 



18. Holland {T. Baker). Salvin-G-odman Coll. 



5. Holland. Lord Lilford [P.]. 

 14. Kassarien River, Esthoaia Seebohm Coll. 



(Russoio). 

 2. Garde See, Pomerania, 26th May Seebohm Coll. 

 (H. Seebohm). 



12. Garde See, 30th May (H. S.). Seebohm Coll. 



Hydrochelidon surinamensis {Om.).\ 

 (Plate XIII. fig. 5.) 



Hydrochelidon nigra surinamensis, Baird, Breioer Sr Ridgw. Water Birds 



N. Am. ii. p. 318 (1884). 

 Hydrochelidon surinamensis, Saunders, Cat. Birds B. M. xxv. p. 20 



(1896) ; Sharpe, Sand-l. i. p. 134 (1899). 



The eggs of the American Black Tern are absolutely undistin- 

 guishable from the eggs of //. leucoptera and H. nigra. 



1. Little Slave Lake, Canada {S. Jones: Salvin-Godman Coll. 

 Henshaw Coll.). 



13. Chicago {C. E. Aiken : Henshav) Salvin-Godman Coll. 



Coll.). 



Genus PHAETHUSA, Wagler. 



Phaetlmsa magnirostris (Lieht.), 

 (Plate XIII. fig. 8.) 



Sterna magnirostris/ Thien. Fortpflanz. ges. Voo. tab. Ixxxii. &f. 6 



(1845-54). 

 Thalasseus magnirostris, Sol. Sr Salv. P. Z. S. 1866, p. 200. 

 Phaethusa magnirostris, Scl. ^ Huds. Argent. Orn. ii. p. 194 (1889) ; 



Saunders, Cat. Birds B. M. xxv. p. 23 (1896) ; Sharpe, Hand-l. i. 



p. 134 (1899). -^ ' 



