SWIFTS. 39 



material in nest-building, as in the genus Collocalia of the Old World, but 

 differently applied. At first sight the saliva appears to have been used merely 

 to secure the foundation of the nest (if the term may be used inversely) 

 to the overhanging projection of rock upon which the rest of the structure 

 is woven, as in the nests of the Icteridce; but, upon closer examination, it 

 will be seen that the saliva has been applied to secure every one of the seeds 

 used in the construction of the nest, and in no other way could so firm and durable 

 a structure be obtained. Another curious feature will be noticed in this nest, 

 which is the false entrance at the side. I remember to have seen a similar thing 

 in other nests. They appear to be placed there to deceive some enemy, such 

 as a snake or lizard, to the attacks of which the parent bird and its off- 

 spring would, during the time of incubation, be more exposed. It would be inter- 

 esting to know how the materials for the nest were gathered, whether from 

 the plant itself, or caught in the air by the bird as the seeds were carried by 

 the wind." 



The seven small species constituting this genus belong to the 

 second subfamily (Chccturinoe), characterised by the elongated wings, 

 and the generally spiny tail, in which the shafts of the feathers are prolonged 

 beyond the barbs so as to resemble needles. The needle-tailed swifts, as the 

 members of the typical genus (Chcetura) are called, are indeed unrivalled in 

 their rapidity of flight. From the other members of the group the edible swifts 

 differ by the absence of the spiny character in the tail ; their chief claim to our 

 interest being their peculiar nests, which form an. article of food in the East. 

 Formed chiefly from the birds' saliva, these nests are firmly attached to the walls 

 of caverns. Mr. C. Hose has discovered that the different species of the genus 

 build distinctive nests; the valuable white nests, which are free from moss, 

 being formed by Collocalia fuciphaga. Writing of the habits of this species in 

 Ceylon, Colonel Legge states that the breeding-season lasts from March till June, 

 and that the nests form large colonies. Many of these are known, from seeing 

 the birds haunt the vicinity of certain precipitous hills, but few have been visited 

 and examined, on account of their general inaccessibility. The narrator then 

 describes his visit to a cave on the 22nd of May, when nearly all the nests 

 contained young, two being the average number. "It is noteworthy that the 

 partially-fledged young, which were procured on this occasion for me, and which 

 I kept for the night, scrambled out on the exterior of the nests, and slept in an 

 upright position with the bill pointing straight up. This is evidently the normal 

 mode of roosting resorted to by this species. The interior of this cave, with its 

 numbers of active tenants, presented a singular appearance. The bottom was 

 filled with a vast deposit of liquid guano, reaching, I was informed, to a depth 

 of thirty feet, and composed of droppings, old nests, and dead young fallen from 

 above, the whole mingled into a loathsome mass with the water lodged in the 

 crevice, and causing an awful stench, which would have been intolerable for a 

 moment even, had not the hundreds of frightened little birds, as they screamed and 

 whirred in and out the gloomy cave with a hum like a storm in a ship's rigging, 

 powerfully excited my interest, and produced a long examination of the colony. 

 This guano-deposit is a source of considerable profit to the estate, the hospitable 



