Miscellaneous. 235 



Mr. M'Nab exhibited several sections of oak-stems found in the 

 course of excavations made at Tanfield, Canonmills, and read the fol- 

 lowing notice supplied by Mr. M'Caul, who had superintended the 

 operations : — " In the course of excavating a pit for a new gasometer 

 nine years ago, a number of oak-stems, the largest 2 feet in diameter, 

 were found. In the pit now excavating, and from 80 to 90 feet from 

 the one alluded to, two fine trees were found. The position they 

 occupied was about 10 feet below the original surface, beneath the 

 lowest bed of gravel, and immediately over the boulder clay, their 

 direction being nearly east and west. Three of the pieces were lying 

 horizontally, and two of thera had a rise towards the east at an angle 

 of 10°. At the western or lower part of these stems, roots in con- 

 nection with them could be traced ; but they mouldered away to the 

 touch." 



A specimen of yellow-flowered Hibiscus, raised by Mr. Isaac An- 

 derson from seeds sent from China by Colonel Eyre, was exhibited. 

 The plant was about 2 feet high and had a woody stem. The leaves 

 are hairy, the petals sulphur-yellow, the flower when expanded being 

 3 to 4 inches across. The epicalyx consists of eight to ten linear 

 sepals, while the calyx consists of two sepals united and thrown to 

 one side. 



A specimen of Hyoscyamus raised from seeds communicated to Mr. 

 Moore of the Chelsea Botanic Garden by Major Madden, was exhi- 

 bited. The plant grows in the Himalaya, and resembles H. albus 

 in some respects. In the open border it attains the height of 2 feet. 

 It has ovate leaves and terminal cymes. The flowers are of a dingy 

 yellow, and the cah'x is covered with glandular pubescence. Dr. 

 Douglas Maclagan tried the efi"ect of the plant on the eye. A single 

 drop of the fresh juice caused dilatation of the pupU in twenty 

 minutes, and the dilatation with shght double vision continued for 

 twenty-four hours. 



MISCELIANEOUS. 



HOLOSTOMUM CXJTICOLA. PI. V. figS. 3 & 4. 



Norwich, June 10th, 1851. 

 To the Editors of the Annals of Natural History. 



Gentlemen, — Shovdd you consider the following notice worthy 

 of insertion in the * Annals,' you will oblige me by its publication. 

 I remain. Gentlemen, your very obedient servant, 



Robert Wigham. 



Specimens of the Bream and Roach have long been observed in 

 the rivers of this part of the country to be frequently covered with 

 black spots, and have been generally considered, when in this condi- 

 tion, to be in a diseased state. I have lately examined these spots 

 with the microscope, and find them to consist of a collection of 

 minute black granules of a branched radiating structure and of a 

 confervoid appearance, and which form the outer coat of cysts con- 

 taining a transparent membranous cyst in which I found an ani- 



