1851.] Linnean Society. 123 



H. cellaria, H. pulchella, Bulimus lubricus, B. obscurus, Azeca tridens. 

 Pupa umbilicata, and Clausilia nigricans. 



The Nottingham Castle-yard contains Helix aspersa, H. hispida, 

 H. nemoralis, H. cellaria, H. rotunduta, Bulimus lubricus, B. obscurus, 

 and Pupa umbilicata. 



Oxton Bog and Warren has Helix fulva, H. lucida, H. pura. Hi 

 pulchella, H. hispida, Bulimus lubricus, Vitrina pellucida, Physa acuta, 

 and Segmentina lineata. 



The Hill Farm at Stanton-on-the- Wolds has Helix hispida, H. 

 sericea, H. depilata, H. concinna, H. fulva, H. aculeata, H. pygmeea, 

 H. caperata, H. ericetorum, H. nemoralis, H. virgata, Bulimus lubri- 

 cus, Carychium minimum, and Vitrina pellucida. 



Read further, a memoir " On the Aquilaria Agallocha, Roxb., the 

 Agallochum or Aloe- wood Tree of Commerce." By the late William 

 Roxburgh, M.D., F.L.S. &c. Communicated by the President. 



The memoir, which appears to have been written in 1810 or 1811, 

 contains a detailed description of this important tree, as well as much 

 other information in addition to that published in the posthumous 

 ' Flora Indica' of the author. The plants described were sent to the 

 Calcutta Botanic Garden by Mr. Robert Keith Dick, Judge and 

 Magistrate at Silhet ; and an extract is given from a letter addressed 

 by that gentleman to Dr. Roxburgh, in which he states that the 

 wood is brought for sale from the country of Kuchar and from the 

 southern parts of the zillah of Silhet, particularly the divisions of 

 Puthureea and Lunglah, where the tree is known by the Bengal 

 name of Tuggur. Its extreme height is from sixty to seventy cubits, 

 and the trunk from two to two and a half cubits in diameter. No 

 part of the wood, except that which is used for the extraction of the 

 Uttur, is applied to any useful purpose. Few trees contain any of 

 this precious perfume, and such as do, have it very partially distri- 

 buted in the trunk and branches. The people employed in its col- 

 lection, however, cut down all the trees indiscriminately, and then 

 search for the Aggur by chopping through the whole tree, and re- 

 moving such portions as are found to contain the oil or have the 

 smell of it. In this state Mr. Dick describes four different kinds, of 

 which the first, called Ghurkee, sinks, and sells at from 12 to 16 

 rupees per seer of 2 lbs. ; the second, called Doim, produces from 

 6 to 8 rupees per seer ; the third, Simula, floats, and is sold at from 

 3 to 4 rupees ; and the fourth, Choorum, in small pieces, which also 

 float, at 1 to 1^ rupees per seer. The oil is obtained by bruising the 



