BH ^^^ Zoological Society^^^^^^^ 



to the bases of the tentacula, interspersed with two or three shades of 

 brown in the form of stripes or spots : in some specimens a circle of 

 very pale spots with darker margins surrounds the mouth. The base 

 of each tentaculum is very dark and is surmounted by a broad band 

 of white or buff, the upper portion shading off to a clear pale pel- 

 lucid brown, on which are three narrow distinct white rings, their 

 breadth and the interspaces diminishing rapidly as they approach 

 the tip. These animals are capable of assuming a great variety of 

 shapes, and even when fully expanded sometimes elongate themselves 

 to the extent of 1| inch, or contract to little more than a :| of an 

 inch. They feed readily in confinement ; but those that had buried 

 themselves in the sand appeared best able to secure their prey when 

 placed within reach, the others on the surface often tumbling over in 

 their endeavours to get the food into a proper position for swallow- 

 ing, from not having the support of the surrounding sand or mud 

 natural to them when buried. They were all found near low water- 

 mark, imbedded in the fine chalky mud which fills the crevices of the 

 rocks at Seaford, their expanded disks being just level with the surface, 

 but so nearly covered that only a faint star-like outline was visible ; 

 on being touched they instantly disappeared ; and so great was their 

 power of inversion and contraction, that on digging carefully, they 

 were generally found about 1 ^ inch deep, and having that peculiar 

 bead-like form which has suggested the specific name of sphceroides. 

 There was usually a depth of 6 or 7 inches of mud below them, so 

 that they could not have been fastened to the rock ; and since I have 

 had them at home, now nearly five weeks, they have not shown the 

 least inclination to attach themselves to the gravel, or glass sides of 

 the tank in which they are living ; three of them have burrowed 

 into some sand on which they were placed, but the others remain on 

 the surface, and are but rarely contracted. Soft mud is probably 

 their natural habitat, being the most easily penetrated, and I could 

 find no traces of any of these animals in a considerable tract of sand 

 only a few yards from the locality whence these were obtained. 



June 12, 18.55.— W. Yarrell, Esq., in the Chair. 



On two new Spectes of Humming Birds. 

 By John Gould, F.R.S. 



I bring before the notice of the Meeting two species of beautiful 

 Humming Birds, which I believe to be new to science : they belong 

 to that section of the Trochilidce to which the generic appellation of 

 Heliothrix has been given ; of this form only three species have 

 been previously characterized, namely H. auritus, II. auriculatus, 

 and H. Barroti. One of these new species, for which I propose the 

 specific name of purpureiceps, is nearly allied to H. Barroti, but 

 differs from that bird in having a much shorter bill, in the blue of 

 the head being of a paler purple, and in that hue not being confined 

 to the crown, but extending some distance down the nape of the 



