102 REVIEWS. 



have made known some facts, which science is not yet in possession of ; or 

 is he aware what " hydroid forms" mean, and that the term " stages," as 

 applied to such organisms, is incorrect, since no metamorphosis, strictly 

 speaking, can be said to occur in these animals. In his account of 

 Laomedea geniculata, he says that " this Zoophyte has the power of throw- 

 ing off the polypi, or, rather, the little polypi are able to detach themselves 

 and still to dance merrily in the water." He makes some quotations from 

 Mr. Gosse, grievously, however, misrepresenting the statements of that 

 naturalist, and then remarks that the polypes " resemble an inverted 

 umbrella, with a nettled disk across its diameter ; on the converse side is 

 a central fleshy protuberance, forming the foot." We believe Mr. Sowerby 

 when he informs us, in the preface, that his " personal observations of 

 Hydroid Zoophytes are very limited." He here confounds the true polype 

 heads of the Laomedea with the medusoids generated in the interior of 

 the productive capsules. The former remain stationary at the top of the 

 stalk on which they were placed, and are the organs by which the Zoophyte 

 procures its nutriment ; the latter are reproductive zoids rendered locomotive, 

 whose functions is to produce ova, which may develope into the likeness of 

 the parent Zoophyte. What Mr. Sowerby calls the " foot" is in reality the 

 peduncle of the medusoid. But this is not all, for " Beroe ovata" is said 

 to have " two very long pendent tentacles, to which are attached, at regular 

 intervals, still more slender threads, which coil like the tendrils of a vine." 

 The truth is that Beroe ovata has no tentacles whatsoever, and that Mr. 

 Sowerby mistakes this ciliograde for Cydippe pomiformis. 



The Zoophytes are described in an exceedingly confused manner, and a 

 definition of these animals is taken from the old edition of Dr. Johnston's 

 work, which is meant to include both Zoophytes and Polyzoa, " Eucratea 

 chelata," Anguinaria spatulata," and " Cellularia ciliata" are placed by Mr. 

 Sowerby among the Hydroid Zoophytes. At page 288 it is implied that 

 Pyrosoma (one of the compound Tunicata) is a veritable fish. 



Many of the animals described are totally unfit for preservation in the 

 aquarium, being either very rare (in some cases not natives of the British 

 islands), or else unsuited to live in confinement. Who would think of 

 keeping a snapping turtle or a crocodile in one's drawing-room, to say 

 nothing of Euplectella Aspergillium, which we would have to send for to the 

 Philippine islands ? or how we are to procure Pavonaria quadrangularis, 

 Arachnactis albida, or Capnea sanguinea, one of which species has not yet 

 been captured on our coast, perhaps, half a dozen times. Mr. Sowerby 

 carries his zeal for rare animals so far as to describe Oculina prolifera, a 



