417 



epoques ci-dessus mentione'es. Je crois que cette nouvelle corre- 

 spondance entre les taches solaires et le magnetisme terrestre, que 

 j'avais deja soup9onnee en 1853 (voir les 'Mittheil. der Nat. Ges. in 

 Bern), suffira pour convaincre les derniers sceptiques qu'il y a une 

 correspondance reelle entre ces deux phenomenes. 



A peine avais-je termine cette recherche et donne a 1' Academic de 

 Paris le meme resume que vous avez hi dans les dernieres lignes et 

 que j'aimerais voir communique par vous a la Societe Royale, que je 

 trouvai dans votre 3 me memoire sur les ' Magnetic Disturbances ' la 

 meme periode decouverte par vous dans ces ' Disturbances.' Je suis 

 bien heureux de vous rencontrer de nouveaux dans mes etudes, et je 

 donnerai dans le 3 me numero de mes ' Mittheilungen,' qui paraitra 

 sous peu, et un extrait de votre lettre du 16 Decembre et la date de 

 votre 3 me memoire. 



IV. " Anatomical Description of a Species of Asteroid Polypes, 

 probably forming the type of a new genus of Alcyonidse." 

 By JOHN DENIS MACDONALD, Assist. Surg. R.N. Com- 

 municated by Capt. DENHAM, F.R.S. Received January 

 13, 1857. 



On leaving the Conway Reef (lat. 21 44' 48" S., long. 174 37' 

 45" E.), July 4, 1855, a very beautiful branched asteroid Zoophyte, 

 belonging to the Alcyonidae, was brought up from a depth of between 

 30 and 40 fathoms, on the buoy-rope of the anchor. 



The polypidom, from a trunk of about one inch and a half in 

 diameter, branched off, with much irregularity, but generally in a 

 dichotomous manner, into very minute subdivisions. 



The investing membrane was strengthened by the close deposition 

 of elongated, fusiform, and minutely tuberculated spicula of a deep 

 crimson-lake tint, which impart their colour to the whole mass. 



The internal substance was chiefly composed of longitudinal mus- 

 cular septa, radiating from the central axis (which contained no 

 denser material), frequently communicating with one another late- 

 rally, and being fixed into the internal surface of the integument iu 

 vertical lines. These muscular septa were invested on each side with 

 a layer of finely reticulated vessels ; both sets being connected by 



