CO 



HARDWICKE'S SCIEN CE-GO S SIP. 



remain quiet for hours in some elegant, graceful 

 position on a rose-spray, and then it would descend 

 and appear restless; its ovipositor, from being 

 horizontal, would become perpendicular, and it was 

 evidently anxious to deposit some eggs ; but, for 

 some reason or other, it failed to do so. On these 

 occasions it avoided the turf, moss, and mould, but 

 it made many little holes in the muslin which 

 covered the perforations of the stand ; and once 

 it pressed its ovipositor with some force on the 

 palm of my hand, but it did not deposit eggs any- 

 where. 



Just fourteen days after its capture the poor little 

 thing died. Whether tlie cause of its death was its 

 failing to deposit eggs, as it evidently_had an in- 

 clination to do, or whetlier it did not get the food it 

 preferred, I cannot tell. I should be very glad to 

 know more of the habits of this interesting insect. 



E. A. M. 



MANNA or THE DESERT. 



AN EDIBLE LICHEN. 



A VALUED correspondent, B. W., having sent 

 me some notes on this production, which he 

 hopes may prove of interest, and elicit further 

 information from some of your readers, I beg to 

 hand them to you, with some additions to the 

 literature of the subject. 





Figs. 41, 42. Lichen esculenttis (barren and fertile specimens). 



Tlie discovery of this curious plant is due to 

 Pallas, who named it Lichen csculentns, and de- 

 scribed and figui-ed it in his great work,"Ileise durch 

 Verschied. Proviuzeu dcs Russischen Reiches," 

 torn. iii. p. 700, T. II. lig. 4 (1770). As this book 

 is not accessible to the general reader, I give copies 

 of the figures, which are of the natural size, and 

 add a translation of his character. "Corpiisculcs 

 free, oblong, composed of a convolute, thick cori- 



aceous white crust, externally wrinkled and tuber - 

 culose, grey or pale ash-colour. Apothecia rare, 

 immersed, excavated, somewhat prominent, like 

 warts. Occurs thickly among stones in the very 

 driest limestone hills of the Tartarian desert, 

 scarcely distinguishable from small stones, except 

 by the expert." In the modern system the plant 

 belongs to the genus Lecanora, and will stand as 

 Lecanora esculenta, Duf. ; Placodium Sustcfii also 

 being a synonym. 



Mr. Berkeley tells us that Dr. Arthaud published 

 a pamphlet to prove that this must have been the 

 manna with which the Israelites were fed, and the 

 same view is supported by Giles Munby, Esq., in a 

 paper", on the botanical productions of the kingdom 

 of Algiers, read at Birmingham in 1849, before 

 the British Association for the Advancement of 

 Science, and published in Annals of Nat. History 

 for Dec. 1849, p. 426. 



Mr. Munby resided many years in Algeria, and 

 be tells us that it covers the sand in some parts, 

 and grows during the niglit like mushrooms, and 

 also that the French soldiers during an expedition 



Fig. 43. Section of the margin of a lobwle, from Algerian 

 specimens, x so. 



south of Coustautirie, subsisted on it for some 

 days cooking it in various ways and making it 

 into bread. 



The specimens received from B. W. were collected ■ 

 at Reboud Djelfa, in the desert south of the Great / 

 Atlas chain, and arc not one-fifth the size of those 

 figured by Pallas : in appearance they precisely re- 

 resemble gum ammoniacum, but are lighter, and 

 and when soaked in water, of a corky consistence; 

 their taste is slightly bitter, and internally they aie 

 of a starchy nature. A section under the microscope 

 shows numerous gonidia imbedded in the th.ck 

 cortical layer a lil tie below the surface. It viU 

 thus be seen that the manna of the desert has 

 notiiiug in common with the manna of our shcps, a 

 saccharine exudation from Fraximts ornus, nc/ with 

 the similar "manna of Mount Sinai" fi;>m the 

 Tamarix munnifcra. / 



Presuming that the lichen is the same a/ that or 



