I7S 



HARDWICKE'S SCIENCE-GOSSIP. 



Trigonocarpon had also an external sheath of an 

 elongated form, giving to it, when this is preserved, 

 an appearance suggestive of a diminutive cocoa-nut, 

 enclosed in its fibrous pericarp. 



Amongst tlic less definite forms of vegetable life 

 preserved in the coal measures are many beautiful 

 petioles, these are peculiarly abundant in some seams 

 in the neighbourhood of Oldham, it is however impos- 

 sible to say to what family of plants they belonged. 

 One of the prettiest of these is Stattropteris Oldhamia, 

 so-called from the star-shaped appearance of its 

 vascular axis in transverse sections. One genus of 

 these petioles, named Zeugopteris, has an axis forming 

 in its sections a sort of double anchor. It is very 

 possible that some of these petioles may have belonged 

 to ferns. 



This short sketch of some of the leading features 

 of the Carboniferous flora is sufficient to have im- 

 pressed upon us its peculiar character. It shows us 

 that, long ages ago, a very strange type of vegetable 

 life overspread immense areas of the globe. From 

 the north pole to the south, over wide regions in the 

 old world continents, and perhaps wider ones in the 

 new, we see that during the lapse of enormous periods 

 of time there must have existed vast tracts of low- 

 lying ground, swamps and moist foggy plains, pro- 

 bably in many cases the deltas of great rivers, where 

 in a warm damp atmosphere the forerunners of our 

 horsetails and club-mosses attained their fullest 

 development, and together with graceful tree-ferns 

 reared their heads over perhaps as numerous species 

 of lowlier growth, whilst dark pine forests clothed the 

 sides of the neighbouring hills. 



It was a period too of many changes : the earth was 

 in a state of unrest, now slowly subsiding and allow- 

 ing the waters to overflow and bury beneath their 

 muddy and sandy sediments the growth of years ; 

 then again a tract here, or a tract there, would 

 gradually rise from below the waters, to be once 

 more clothed with vegetation, to be again in its turn 

 submerged, preparing the way for a fresh growth, and 

 so on from age to age. 



Uut we need not suppose that the same species 

 were always found together, nor that at each succeed- 

 ing stage the same kind of plants reappeared. 



Many species belonging to the Carboniferous period 

 never grew together ; change also and modifications 

 of type took place then as in later ages. And during 

 the long course of centuries old forms would disap- 

 pear, to make room for newer which should occupy 

 their place. At one time we might have seen ferns 

 and Sigillarias flourishing over a district, when at a 

 later date licpidodendra and Calamites would alone 

 be found. And even though there might not be any 

 very great changes of genera still the species would 

 be ever undergoing modification through varying 

 conditions. In consequence of changes of this nature, 

 we may now frequently find in one bed of rock a 

 certain set of fossil species, whilst in an overlying one 



some only of these will be repeated, and with these 

 we may find an introduction of new forms ; and it 

 has been remarked that but few species are continuous 

 through the whole series of beds ; it follows from this 

 that a knowledge of some of the plants characteristic 

 of the different horizons in the Carboniferous rocks, 

 as well as of other organic forms would, in the absence 

 of other indications, be highly useful to the mining 

 engineer in tracing a seam of coal in an area that had 

 been much disturbed by faults. 



Summing up in conclusion the 'known number of 

 species of plants hitherto found in the coal measures, 

 we obtain the following approximate figures, worked 

 out from Schimper's catalogue ; to these some few more 

 may have to be added, whilst on the other hand it is 

 probable that, in more than one or two cases, frag- 

 ments of one and the same plant have been separated 

 by different names. That such a list, after all, should 

 represent more than a fraction of the entire Carbon- 

 iferous flora is more than we can suppose ; large as 

 the number of plants is that has thus been recovered, 

 there must yet have been a still larger number of 

 which no trace has as yet been found, of many of 

 which, perhaps none, has even been preserved. 



Further research and study will doubtless enlarge 

 the list, and a careful collection and investigation of 

 the numerous remains that are constantly being 

 brought to the surface in new sinkings for coal would 

 most certainly abundantly repay any one who would 

 devote the necessary time and attention to this most 

 interesting branch of Paloeontological research. 



NOTES ON DAMPING THE PUP^ OF' 

 LEPIDOPTERA, WITH OBSERVATIONS 

 ON THEIR MANAGEMENT IN CONFINE- 

 MENT. 



By William J. V. Vandenbergh, F.M.S., &c. 



IT has always been a disputed point with lepidop- 

 terists as to whether the puprc of the majority of 

 species of our lepidoptera require, or do not require, 

 to be damped when in confinement. 



It is undoubtedly a fact that by far the best way tO' 

 successfully rear our pupa; is to place them in such a 

 position that they may be, as far as possible, under 

 natural meteorological conditions ; but to carry this 

 out thoroughly, is, to say the least, a matter of con- 

 siderable difficulty. 



The reason for keeping our captive pup^e in close 



