Mr. R. Warington on the Aquarium. 313 



Class ZOOPHYTA. 



Order Actinoida. Fam. LucERNARiADiE. 



Genus Lucernaria (Miiller). 



L. campanulata (Lamx.). 



A specimen of this species was obtained at Ilfracombe in 

 August, by the Rev. Sir Christopher Lighton, who kindly gave 

 it to me. It was about 1^ inch in height, of a dull chocolate 

 hue, in parts tinged with olive ; in form a deep goblet with the 

 cup slightly bell-shaped, the stalk slender, and the foot wide and 

 thick : the groups of tentacles were contracted while I had it, 

 the globose heads being crowded together, with no appearance 

 of their slender pedicels. Between the tentacled eminences the 

 spaces were rounded, and seemed as if the integument were a 

 little turned over like a rim. 



It was found attached to a sea-weed, but soon detached itself, 

 and never afterwards adhered to anything : the only motion I 

 observed in it was an occasional spasmodic bending-in of one or 

 other of the tentacle-groups. After a day or two it became 

 oflfensive, without losing its form, and was evidently dead and 

 decaying. 



EXPLANATION OF PLATE VIII. 



Fig, 1. Pachygnathus notops, magnified, dorsal surface. 



— 2. Ibid, the lip viewed from beneath. 



— 3. Ibid, the palpi and styliform mandibles. 



— 4. Ibid, an unguis. 



— 5. Crithida thalassina, magnified. 



— 6. Acineta, parasitic upon a marine Mite, magnified. 



— 7. Crossostoma Midas, nat. size, out of its tube. 



— 8. Ibid, magnified, viewed laterally, with a portion of its tube. 



— 9. Ibid, magnified, viewed dorsally, anterior portion. 



— 10. Ibid, a foot from near the middle. 



— 11. Ibid, the posterior extremity, and caudal styles. 



— 12. Ibid, a pencil of bristles. 



XXVIII. — On the Injurious Effects of an excess or want of Heat 

 and Light on the Aquarium. By Robert Warington, Esq. 



Temperature is a point requiring great attention in carrying 

 out successfully the principles of a permanent aquarium. The 

 mean temperature of the ocean is estimated to be about 56° Fahr., 

 and this, under ordinary circumstances, does not vary more than 

 about 12° throughout the different seasons of the year. The 

 causes of this equilibrium will be readily understood when we 

 take into consideration the effects that must be produced by the 



