LEAVE OF ABSENCE. Ill 



colour of Callitliamnion ; and however unimportant colour may- 

 be in other plants, you know that in the Algae it is usually 

 considered of first-rate value. Alas, that it should be so 

 fugacious ! for some of the specimens, as you will perceive, have 

 faded into a dirty green, from which it passes to white. In its 

 green state it might be taken for a Spliacelaria, and indeed closely 

 resembles S. Callitriche of Agardh, from the Falkland Isles, so 

 much so that I almost fancy Agardh had a faded plant ; but of 

 this there is no proof. However, there can be no question 

 that if Agardh had a specimen in its red or original state, he 

 would make a genus of it, as I have done, and place it among 

 the Ceramieee. I have seldom met with a more beautiful 

 microscopic object, and strongly advise your putting up in 

 Canada balsam some fragments — the best coloured you can find. 

 It keeps its extreme beauty under a high power, and has already 

 delighted our chief microscopists in Dublin, and will, I doubt not, 

 equally delight your club. Mind to moisten the specimen so as 

 to expand the tissues before examination. The collection con- 

 tains several very pretty and some curious things, and makes me 

 long more than ever for a ramble on those Australian shores 

 which have been so long the object of my dreams and wishes. 

 I go to Limerick in a day or two, and shall be glad to hear from 

 you there what Brown says of this Alga. 



I am getting on but slowly with the " British Algae." These 

 dark short days one can do but little, and my eyes will not bear 

 the microscope at night. In the country I shall work with 

 greater ease. 



To a Cousin. 



Dublin, March 14, 1840. 



The time for my departure for Ausonia approaches — Egypt 

 is given up. We go only to Italy, amongst whose modern ruins 

 (modern compared with Egypt) there be many things to arrest 

 one. 



I got, a few days ago, my long-expected parcels from Mrs. 

 Griffiths, from Assam and Birman Empire, amongst which are 

 many beautiful objects, and some rarities ; many ferns, of which 

 one is Kaulfussia assamica, a very singular but by no means 

 pretty plant. 'Tis not unlike a leaf of Cow Parsley, but its fruit 

 is very curious. 



