May 2, 1898.] 



KNOWLEDGE 



101 



Of course we devoted much attention to Calamocichla 

 brevipinnis, and secured a fine series of this rare warbler, 

 together with a couple of nests containing eggs. This 

 species exhibits all the habits of a true reed warbler. 



Though concealed from view, in yonder group of coffee 

 bushes there is a pair. Ever and anon the male bird 

 tempts his mate with song. First of all the male bird 

 begins by uttering a soft, melodious " chou " several times 

 in a deliberate and slow manner, and this call is responded 

 to in a similar way by the female ; and then the male, as 

 if assured of her attention, pours out his string of exquisite 

 notes. The first three notes are uttered with marked 

 feeling and a pause follows, after which the remaining 

 notes are given out in quick succession and in a higher 

 key — a pretty, mellow trill being given to the last one. 



This song is not unlike that of our reed warbler {Acroce- 

 phalus streperwi), but it is of far finer quality, though not 

 so rich in notes. English reed beds are not conducive to 

 fine singing. A chilly atmosphere pervades them, while 

 the reeds themselves tremble and commence to jostle one 

 another at the mere mention of the wind's coming. And 

 amid such disturbing influences the reed warbler utters his 

 song, which at times becomes discordant and shrill as 

 though he were shouting to the reeds to keep quiet. 



But the other reed warbler (C. brcviptiinis) pours out 

 his song under peaceful and lethargic influences. The 

 leaves hardly as much as stir ; a tropical heat pervades 

 the passages of the cofl^ee groves, and imparts to the bird 

 just that amount of languor which makes him utter his 

 song with soft deliberate feeling, coaxing forth the notes, 

 as it were, till they become round and mellow — a song, 

 truly, that haunts the memory. 



The nest, figured here, is of a deep cup-shaped form, 



Xest of Calamocichla Irevipennis in a Coffee Tree. 



and bound to two or more of the upper stems of a cofi'ee 

 bush or of a young orange tree, and about eight or nine 

 feet from the ground. 



Fine strips from the dried-up blades of the maize plant, 

 dead grass, and the fibrous rind from the trunk of the 



banana tree compose the body of the nest, while fine 

 grass and bents form the lining. 



The eggs, generally three in number, are bluish white, 

 spotted and blotched all over (but more thickly at the 

 larger ends) with pale brown and purplish brown, with 

 underlying blotches of violet grey. 



Their dimensions correspond with those of the round 

 form of our reed warbler. 



Round about this valley a species of owl {Strix insulaiis) 

 is met with. It is a very beautiful bird, and is closely allied 

 to our common bam owl {Stri.r jfammea). A deep fawn 

 colour takes the place of the white in the latter, while 

 its upper parts are suffused and marked with a rich French 

 grey. It is by no means common, and we found it a 

 matter of great difficulty to induce the natives to search 

 the tops of cocoanut trees, in which these birds generally 

 live. They look upon this owl with superstitious fear, 

 believing that a wound from its claws never heals. 



On returning home, as we entered the outskirts of 

 Stancha, a company of Egyptian vultures arrested our 

 attention. They gave us a lazy glance, and then stared 

 in the opposite direction. 



In spite of their repulsive habits, one cannot help 

 possessing a sneaking regard for these birds with their 

 wrinkled faces of the colour of yellowed parchment, for 

 one somehow feels that they are old and venerable, and 

 have outlived many a human life. 



The birds find plenty of food about Stancha. Every 

 morning, as regular as clockwork, they troop towards the 

 slaughter-house and then return the same way — only a 

 little slower this time — to an old place of rcnile-.nius outside 

 the town, where they indulge in siista.-^, now and again to 

 awake, to ponder, perhaps, upon what the nature of the 

 next " kill " would be in yonder house. 



During the breeding season, which is generally in 

 December, they cease to haunt the villages, and betake 

 themselves in couples to lofty hill ranges ; and then they 

 appear again in the vicinity of dwellings with their young 

 as February comes round. 



The Cape Verde Islands are the westernmost range of 

 this species. 



Above the heads of the vultures, enjoying a pure atmo- 

 sphere, resided a number of ravens (Comts umbrhuis) that 

 cawed lustily from time to time. 



It is very interesting to have discovered this raven, with 

 the brown head and neck, on Sao Nicolau, as the species 

 was considered by ornithologists to have its westernmost 

 range in Egypt. 



With another hour gone by the light of a brief twilight 

 commenced to creep over the plains and then down into 

 the valley, while the distant hills were suffused with a hue 

 like the purple bloom on a grape. And then, as twilight 

 glided into dusk, the stillness was broken by the locusts, 

 who vamped incessant accompaniments to the soft music 

 of night. 



DESERTS AND THEIR INHABITANTS. 



By E. LrDEKKEB, b.a., f.r s. 



IP popular errors connected with matters scientific are 

 hard to kill, stiU more is this the case when the 

 erroneous opinions have been held by scientists 

 themselves. The idea that flints and other stones 

 grow is, I have good reason to believe, still far from 

 extinct among the non-scientific ; and it is not improbable 

 that there are persons possessing a more or less intimate 

 acquaintanceship with science who still cherish the belief 

 that deserts are uninterrupted plains of smooth sand, 

 originally deposited at the bottom of the sea, from which 



