4 ME. T. SCOTT ON ENTOMOSTEACA 



Among Algte specially noteworthy were the exuberant growths of Corallinge near 

 Las Palmas, attached to a soft sandstone on a narrow isthmus joining the volcanic 

 sections of the island, and of Pad'ma (Adanson) on the beach, about 3 miles from Dakar, 

 at the far side of the bay surrounding Goree Island. 



Per the preservation of zoological specimens the following means were at hand : — 

 methylated spirit, alsolute alcohol, glycerine, benzole, ether, chloroform, acetic acid, 

 ammonia, hydrochloric acid, sulphuric acid, nitric acid, corrosive sublimate, caustic 

 potash, osmic acid, chromic acid, j)icric acid, iodine, picrocarmine, hsematoxylin, Canada 

 balsam; with accessories such as slides, cover-glasses, watch-glasses, porcelain dishes, 

 spirit-lamj), camel-hair brushes, needles, spatulas, two nets of varying degrees of fineness, 

 a tank-box, shrimp-ti*awls, mud-bags, and specimen bottles. Some 200 bottles of 4-oz. 

 capacity, in addition to several boxfuls of others of larger sizes. At the end of the work 

 all the available bottles were filled, and as many others as could be obtained empty from. 

 the supplies of the ship. 



Many micro-preparations were made of the products of the soundings, of which 411 

 were taken during the cruise, and of the contents of the tow-nets at various points. 

 Larger specimens, such as species of Pisces, were procured from native fishermen at 

 St. Paul de Loanda, and for these the tank-box proved very u.seful. Larger Crustacea, 

 of which a few were fouud on shore, were preserved in spirit at once. Numerous shells 

 of Mollusca were obtained dry ; but one of the most important departments of the work 

 was the preservation of the more delicate Arthropoda (Copepoda, Amphipoda, Schizopoda, 

 &c.), Ascidia, ova, fish-larvce, Sag'Uta, &c., found in the tow-net gatherings. Por these the 

 methods adopted were essentially those practised at the zoological stations of Naples * and 

 elsewhere. Por delicate objects, Prof. E. R. Lankester had recommended, in a letter to 

 Dr. John Murray, two plans : (a) corrosive sublimate followed by dilute then stronger 

 alcohol, and (/3) ^ per cent, osmic acid, or this mixed with very dilute chromic acia 

 or acetic acid, giving a short exposure of 1 to 2 minutes according to size : this to be 

 followed by alcohols of increasing strength. The latter method was recommended for 

 Olione and other Pteropoda ; it was adopted but rarely, owing to the difficulty of prose- 

 cuting many different methods in a limited amount of space (the laboratory at command 

 being quite small, but very compact) the combined chrom-osmic or aceto-osmic plans 

 were not tried at all : the former method was freely used. For the Radiolaria the osmic 

 acid process also proved of use, it had been recommended by Hartwig and by Haeckel ; 

 but a glycerine medium to follow it was not employed because of the unsuitability of 

 its refractive index to that of the E-adiolarian skeleton. 



For preserving the products of the tow-net pure alcohol was never adopted ab initio, 

 but acidulated alcohol was tried, following the directions of Paul Mayer and Whitman, 

 viz. 70 or 80 per cent, alcohol with a small addition of pure hydrochloric acid and a trace 

 of picric acid. The specimens were subsequently washed with strong spirit to remove 

 the acid, and preserved in spirit. Again, the picrosulphuric acid method following 



* Mayer, Mittheil. zool. Stat. Neap. ii. (1S31) p. 1 ; Journ. Eoy. Micr. Soc. u. s. ii. (1882) p. 866. 



