NEWLY-DISCOVERED HABIT IK THE BLACKCAP WARBLER. 9 



the day, tear the calyx across. This could only cause an exuda- 

 tion of sap which might attract insects, but could not serve a3 

 food for the bird. So far as the Hibiscus is concerned, it is 

 scarcely credible that the nectar is the sole object sought by the 

 bird. At any rate, it is obvious that it takes advantage of its own 

 act to secure insect food. Whether this is the primary object is 

 not so clear. It may be that the Blackcap is a nectar-eating 

 bird, though there are no observations to show this. I certainly 

 think it very probable that the Garden Warbler punctures 

 G, antholyza for the purpose of obtaining the nectar, in the first 

 instance; but in the case of Abutilon, I cannot believe that 

 Parus would search for nectar ; and very clearly I think the 

 laceration of the calyx was made with the object of enabling the 

 ants to reach the nectary. Phylloscopus may possibly be a nectar- 

 eater, but this is doubtful. It certainly does not tear the flowers, 

 and only acts as a poacher, visiting the flowers torn by other 

 birds for the purpose of taking its insect prey. An interesting 

 example of this kind of poaching is given below.* 



(2.) How far is the habit of puncturing the flowers and after- 

 wards searching for the insects an acquired one ? The puncturing 

 is common with true nectar-eating birds — Zosterops, Nectarinia, 

 and others. My friend Dr. Percy Kendall says of Cinnyris sene- 

 galensis : — " Scarcely a flower in my garden yielded any flowers the 

 corollas of which had not been pierced by individuals of this 

 species" (" Ornithology of the Gambia," ' Ibis/ April, 1892). 



* Mr. N. B. Moore has made observations at the Bahamas on the 

 Certhiola flaveola, which obtains nectar from the flower of Verea crenata 

 by thrusting its bill at once through the petals into the nectary. It is only 

 after the bird has made an opening that black ants are found in the 

 nectary. But these birds also poach on the Woodpecker's preserves. One 

 day Mr. Moore observed a Picus varius extracting sap from a logwood 

 sapling, and as the Woodpecker flew away two Certhiolce appeared, perched 

 near the sapling from which the juice was oozing, and by cunningly thrusting 

 in their penicillate or bristle-tipped tongues commenced to lap or suck the 

 fluid into their mouths. This practice was constantly observed afterwards. 

 Mr. Moore fixed the bowl of a teaspoon in a fork of the same tree and placed 

 some strained honey in it. In three days the Certhiolce found this, and 

 commenced to feed on it. They were followed by another bird, Dendrceca 

 tigrina, and other species, which also attacked the Woodpecker's sap-pits* 

 These are interesting instances of apparent intelligence on the part of birds. 

 (Proc. Boston Soc. Nat. Hist., Jan. 1878). — From ' Nature,' April 25th 

 1878, p. 509. 



