262 Rev. S. Haughton on the Muscular Mechanism 



hydrorhiza, the whole invested by a chitinous periderm. 

 Polypites issuing from the distal- extremity of the tubes, 

 claviform, with scattered filiform tentacula. 

 Gonosome. — Gonophores consisting of mulberry-like masses 

 of sporosacs supported on short gonoblastidia, which arise 

 from short tubular openings in the hydrorhiza. 



Merona Cornucopia, Norman (species typica). 



Tubiclava Cornucopia, Norman, Ann. Nat. Hist. ser. 3. vol. xiii. p. 82, 

 pi. 9. figs. 4 & 5. 



In the ' Annals ' for January 1864 I described and figured a 

 Hydrozoon from Shetland under the name of Tubiclava Cornu- 

 copia. The species was thus assigned by me to a genus which 

 had been recently established by Professor Allman, because it 

 agreed in all essential particulars with the type-species T. lucerna, 

 except that the gonophores in T. lucerna were described as 

 " dense clusters of sporosacs aggregated immediately behind the 

 posterior tentacula" but in T. Cornucopia they are dense clusters 

 of sporosacs aggregated on short gonoblastidia arising from the 

 hydrorhiza. It then appeared — and, indeed, still appears — to 

 me questionable whether the exact position of the gonophores 

 is a sufficient ground on which to establish a genus. I there- 

 fore thought it desirable that the generic character of Tubiclava 

 should be extended so as to embrace the new form which I 

 had met with. Professor Allman, however, prefers to retain 

 his genus within the limits originally assigned to it, and, both 

 by letter and in his paper " On the Construction and Limitation 

 of Genera among the Hydroida" (Ann. Nat. Hist. ser. 3. 

 vol. xiii. p. 345), has given it as his opinion that my T. Cornu- 

 copia is the type of a new genus, which is here therefore esta- 

 blished under the name Merona. 



Houghton -le-Spring, 

 March 13, 1865. 



XXIX. — On the Muscular Mechanism of the Leg of the Ostrich. 

 By the Rev. Samuel Haughton, M.D., F.R.S., Fellow of 

 Trinity College, Dublin. 



[Plates VI. & VII.] 



On the occasion of the death of the fine male Ostrich during 

 the month of January 1864, in the Zoological Gardens of Dublin, 

 I secured the body for dissection in Trinity College, and re- 

 quested Mr. Macalister, of the Royal College of Surgeons, to 

 avail himself of the opportunity thus afforded of completing the 

 anatomical investigations he had previously commenced, in the 

 Royal Dublin Society, by the dissection of the female Ostrich 



