31 



15. * Black Tern, Sterna nigra, Linn. Mr. Ball has seen this 

 bird in tlie month of July, for some years successively, at Roxborough, 

 near Middieton, co. Cork. 



Jn addition to these I may mention the 



1 6. * Blackcap H'arbler, Curruca atricapilla, Bechst., which, though 

 stated in Rutty's Dublin to be frequent in that county, admits of some 

 doubt, as more than one species is commonly called by the name of 

 Blackcap in Ireland. On the 1st March, 1834, I saw, in the shop of 

 Mr. Galbraith, Bird Preserver, Belfast, a fresh specimen of an adult 

 male Blackcap, which had been killed (probably the day before) in the 

 garden at Down and Connor House, co. of Down. 



Other individuals of the species marked thus * have been recorded 

 in the MS. Catalogue of the late J. Templeton, Esq.— W. T. 



Mr. Thompson also stated that specimens of the true Lestris para- 

 siticus, Temm., have repeatedly occurred in the Bays of Dublin and 

 Belfast. He added, that during the great storm which took place on 

 the 31st August, 1833, a great many specimens of the Octopus octo- 

 podia (which hud not before been recorded as occurring on the shores 

 of Ireland) were thrown ashore in Belfast Bay. 



Mr. Owen read a Paper " On the Structure of the Heart of the 

 Perennibranchiate Amphibia, or Reptiles douteux of Cuvier." 



He briefly noticed the progressive discoveries relating to the heart 

 of Reptiles which have been made since the time of Linnaeus, and 

 which have successively rendered inapplicable to the Saurians, Cheloni- 

 atis, and Ophidians, the phrase " Cor uniloculare, uniauritum", applied 

 to the whole of the Reptilia in the ' Systema Naturce'. He alluded to 

 the researches of Dr. Davy and M. Martin St. Ange on the structure 

 of the heart in the Caducibranchiate Amphibia, from which it appeared 

 that two auricles were appended to the ventricle in those Reptiles, as 

 well as in the higher orders above mentioned. He then proceeded to 

 give the results of an examination of the hearts of specimens of Am- 

 phiinna, Cuv., Menopoma, Harlan, Proteus, Schreib., and Siren, Linn. 

 He selected the heart of the Siren lacertina as the subject of detailed 

 description, considering that the genus Siren, in combining with per- 

 sistent external branchice a limited number of extremities, exhibits the 

 simplest form of the Amphibious Reptile. 



The heart in this species consists of three distinct cavities, as in the 

 higher Reptilia, viz. of two auricles and one ventricle. The auricles 

 appear to form externally one large and remarkably fimbriated cavity, 

 situated behind, and advancing forwards, on both sides of the ventricle 

 and bulbus arteriosus. The venous blood is poured into a large mem- 

 branous sinus by one posterior and two anterior vente cava prior 

 to passing into the auricle. The conjoined trunk of the pulmonary 

 veins appears also to enter this sinus, but it passes through without 

 communicating with that cavity, and terminates in a small separate 

 auricle, which opens into the ventricle by an orifice distinct from, but 

 close to, the orifice of the right auricle. In the ventricle a rudimen- 

 tary septum was noticed as affording an indication of a type of forma- 



