205 



Dr. R. yon AYilleinoes-Suum on a new [Mar. 6 3 



be employed as a dye ; and the oil gives colours of various tints when 

 treated with other oxidizing agents, according to the usual reactions of 

 methyl-aniline. The red- violet from the arsenical melt may, after puri- 

 fication, be converted into the bluer shades by the Hofmann process, when 

 a new generation of gum is again observed. 



The specific gravity of the methyl-aniline oil has varied a little in dif- 

 ferent operations, but keeps within the ranges of 0-95 and 0-97. It is 

 probable that this trifling variation may be ascribed to admixtures of di- 

 methyl-aniline, due in part to the introduction of higher methylated pro- 

 ducts into the crude gum employed in these experiments. 



By operating in a similar manner upon the ethyl gums the corresponding 

 ethyl-aniline has been obtained, the boiling-point of which was higher and 

 not so definite (205°-210° C.) as in the case of the oil already described. 



By way of conclusion, and as giving further proof towards establishing 

 the identity of the new oils with ethyl- and methyl-aniline respectively, 

 it may be stated that they fail to give Girard's blue when heated with 

 rosolic acid or rosaniline, but take the peculiar course of changing slightly 

 towards violet, and then suddenly becoming decolorized, — reactions almost 

 without parallel in the history of the tinctorial aniline derivatives. 



[Specimens of the so-called Hofmann gum, of the ethyl-aniline and 

 methyl-aniline oils, and skeins of silk and cotton dyed with the reddish 

 (or primitive) violet made from the latter, accompanied this communica- 

 tion. — J. S.] 



III. (< On a new Genus of Amphipod Crustaceans." By Rudolph 

 vox Willemoes-Suhm, Ph.D.; Naturalist to the ' Challenger 3 

 Exploring-Expedition. Communicated by Prof. TVyville 

 Thomson, E.R.S.,, Director of the Civilian Scientific Staff of 

 the Expedition. Received February 27, 1873. 



(Abstract.) 



In lat. 35° 47', long. 8° 23', off Cape St. Vincent, the trawl was sent 

 down to a depth of 1090 fathoms on the 28th of January, and brought 

 up, among other very interesting things, a large transparent Amphipod 

 with enormous faceted eyes. The animal, evidently hitherto unknown, 

 will be the type of a new genus, having the following characters : — 



Tuaumops, nov. gen. 



Caput oblongum, inflatum, oculis maxim is superiorem capitis partem 

 tegentibus. Segmenta thoracica 6, abdominaha 5. Antennarum in 

 feminis par unum, maxillarum par ununi, pedum paria duo minima 

 maxillarum locum tenentia. Mandibular nulla). Pedes thoracici 5, 

 abdominales 3 in quoque latere. Appendices caudales 4. Gangli- 

 orum pectoralium paria 5, abdominahiun 3. 



