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XII. Observations on Entozoa, with notices of several new species, including om accotmt 

 of two experiments in regard to the breeding of Taenia serrata and T. cucumerina. 

 £1/ T. Spencer Cobbold, M.J)., F.L.S. 



Read December 3rd, 1857. 



IN the month of February 1856, I commenced some experiments with the view of con- 

 firming the statements of continental helminthologists in regard to the development and 

 habits of the cestoid Entozoa. Unforeseen cii'cumstances prevented my carrying out these 

 investigations to any great extent ; nevertheless, as I have, during my past connexion 

 with the Anatomical Museum of the University of Edinburgh, collected and examined 

 numerous forms of Entozoa, I desire to lay before the Society the restdt of these casual 

 searchings, at the same time offering an apology for the necessarily incomplete and frag- 

 mentary character of my remarks. 



Excluding Man, the number of vertebrate species examined by me, with especial refer- 

 ence to the presence or absence of Entozoa, amounts to seventy, in forty-five of which 

 worms were detected. This proportion, however, must not be regarded as a fair criterion 

 of the frequency with which these higher orders of animals are infested ; for although a 

 great number of individuals — from twenty to forty — of the common species were examined, 

 only one or sometimes two of the species more difficult to procure came under notice. 

 In a statistical point of view, certain particulars in regard to the age of the animal, the 

 time that had elapsed after death before it was examined, and other conditions materially 

 lessening the chances of the detection of Entozoa, would have to be taken into considera- 

 tion. The forty-five species found to contain worms may be arranged as follows : — 



I 



Common Stickleback, Gasterosteus aculeatus. 

 Fifteen-spiiied Stickleback, G. spinachia. 

 Minnow, Leuciscus phoxinus. 

 Rockling, Motella quinquecirrata. 

 Viviparous Blenny, Zoarcus viviparxis. 

 Smooth Blenny, Blennius pholis. 

 Lucky Proach, Coitus bubalis. 

 Haddock, Morrhua mglefinus. 

 Coal-fish, Merlangus carbonarius. 

 Cod, Morrhua milgaris. 

 Ling, Lota molva. 

 Holibut, Hippot/lossiis vulgaris. 

 Skate, Raia batis. 

 Pipe-fish, Syngnathus acus. 

 Angler, Lophius piscatorius. 

 Sun- fish, Orthagoriscus mola. 

 Sturgeon, Acipenser sturio. 

 VOL. XXII. 



Toad, Bttfo vulgaris. 



Frog, Rana temporaria. 



Lesser Newt, Lissotriton punctaitts. 



Serpent, Bothrops ? 



Kite, Falco milvus. 

 Kestrel, F. tinnunculus. 

 Peregrine, jF". peregrinus. 

 Sparrow-hawk, Accipiter nistts. 

 Honey Buzzard, Pernis apivorus. 

 Long-eared Owl, Strix otus. 

 Redshank, Totanus calidris. 

 Curlew, Nurnenius arcuata. 

 Grey Gull, Larus glaucus. 

 Kittiwake, L. tridactylus. 

 Guillemot, Una troile. 



