QQ HOOKER. — BOTANICAL INSTRUCTIONS. 



treated in the same way as the pancake-ice it yielded an abundant 

 harvest. YII. The mud and other soundings from the bottom of 

 the ocean, when brought up on the arming of the deep-sea lead, 

 or the chlam or dredge, generally contain the siliceous skeletons 

 or coatings of many species, with the markings of their surface 

 retained. VIII. The fresh and salt waters and muddy estuaries 

 of the Falkland Islands, and similar localities present us with 

 species, occurring under circumstances altogether similar to what 

 accompany their allies in Eui'ope, and are caught by the dredge as 

 it comes up." 



Note Algae on ships, &c., with the submerged parts in a foul 

 condition ; also preserve scrapings of coloured crusts or slimy 

 matter, green, brown, &c. 



Observe Algas floating, collect specimens, noting latitude and 

 longitude, currents, &c. 



Examine loose floating objects, drift-wood, &c., for Algae, if 

 no prominent species presents itself, preserve scrapings of any 

 coloured crusts, note as above. 



It might be useful to have a few moderate sized pieces of 

 wood, oak, &c., quite clean at first, attached to some part of the 

 vessel under water to be examined, say, monthly. The larger or 

 shorter prominent Algae should be kept and noted, and crusts on 

 such examined and preserved, with notes of the vessel's course. 



Various instances have been mentioned by travellers of the 

 coloration of the sea by minute Algae, as in the Straits of Malacca 

 by Harvey ; and cases of this kind would be worth special attention. 



The calcareous Algae {Melobesia, &c.) are comparatively 

 little known and are apt to be overlooked, they probably do not 

 inhabit the Polar area, but their northern distribution is undeter- 

 mined. 



Fresh-water Algae should be collected as occasion presents. 

 Prof. Dickie states that they may be either dried like the marine 

 kinds, or preserved in a fluid composed of three parts alcohol, two 

 parts water, one part glycerine, well mixed. 



Cases are recorded of the presence of Algse in hot springs. 

 If such are met with the temperature should be noted and specimens 

 preserved. 



Mr. William Archer, of Dublin, has supplied the following notes 

 on collecting Diatoms, &c. in Ireland, and which probably apply 

 equally to various Polar localities where water stagnates. 



" In these lands the nicest Algae are those found in peaty dis- 

 tricts, not in peat-bogs, but in uncultivated spots with a peaty 

 bottom, on the edges of springs, and this in spring and summer 

 when the species are found in conjugation or in fruit. Desmidiese 

 are met with far more abundantly in such spots either mixed with 

 conferva© or crowded into cloudy masses on dead leaves, or (the 

 larger kinds) forming a mucous stratum. The collecting a 

 little of such material from many sites ofiers the best means of 



