30 



THE NATURALIST. 



steeper as the path degenerates into a mere bridle road running through the 

 vineyards which produce the wine called Lachryma Christi. Amongst the 

 decomposed scoriae and ashes forming the soil of these vineyards a pretty red 

 Lychnis was growing abundantly; on the walls bounding the road I observed 

 the following ferns : — Gmmmitis Ceterach, Gymnogramme le;ptophylla, 

 Asplenium Tricliomanes, and A. adiantum-nigrum, Polypodium vulgar 

 and Adianthum Capillus-Veneris. As we advanced the vineyards dis- 

 appeared and beds of Spanish broom in fuU. flower usurped their place. These 

 too were left behind and nothing broke the desolate plains of scoriae and 

 ashes but scattered plants of Artemisia — Glaucium — a Silene with white 

 flowers, and a Scrojplmlaria, with pinnate leaves and small purple and green 

 blossoms. — On this plant I saw the larva of some species of CucuUia, while 

 now and then a specimen of Macroglossa Stellatarum would career wildly 

 over the desert waste — we now reached some old streams of lava covered 

 with scoria, and winding round them reached the base of the cone. As the 

 horses could go no farther we dismounted and leaving them behind began the 

 last ascent. As this part is rather steep, and owing to the crumbling nature 

 of the soil very tiring, a jportantina or chair with four bearers is necessary 

 for ladies, and accordingly one was in readiness. After two or three rests 

 we at length gain the summit of the crater. I am afraid that any descrip- 

 tion of mine would fail to give an idea of the true appearance of this 

 interesting place. I shall however describe it as well as I can, but before 

 doing so it may be as well to give a little of the history of the mountain. 



Vesuvius and Monte Somma (a neighbouring peak rising from the same 

 base) were originally one mountain, known as Mons. Summanus, and 

 recognised by the ancients as a dormant volcano. In A.D. 79, the eruption 

 occurred which destroyed Pompeii and Herculaneum, broke down three- 

 fifths of the crater Mons. Summanus and produced the cone now known as 

 Mount Vesuvius. The remaining two-fifths of the crater of Monte Somma 

 surrounds by a semicircle to the north and east, the cone of Vesuvius ; and 

 it has been ascertained that if this segment of a circle was continued, that 

 the present Vesuvius would occupy the exact centre. The height of Monte 

 Somma, is 3.747 feet and between it and Vesuvius lies a semicircular plain, 

 covered with larva and scoria, called the Atrio del Cavallo. Vesuvius varies 

 in height after every eruption. Its present altitude is about 4,169 feet. To 

 return now to my description. On gaining the edge of the crater we saw 

 before us a deep hollow with precipitous sides formed in some places of rocks 

 covered with yellow sulphur and quite perpendicular, in others of reddish 



