HARDWICKE'S SCIENCE-GOSSIP. 



187 



•display of the larva, pupa and imagos of Apoiiia 

 ■CratiEgi and their ichneumons, the cocoons of which 

 Mr. Watkins tells his visitors are frequently called by 

 gardeners "caterpillars' eggs." In another cage a 

 number of ant lions which are very lively, puffing the 

 sand from their curiously-constructed traps. In 

 different cages are also to be seen in all their stages, 

 Aitacus Cccropia, Attaciis Cynthia, Attacits Pernyi, 

 Saturnia pyri, and Actias hina. Some forcing must 

 have been necessary to show, as Mr. Watkins does, 

 many of these species spinning up at this early period 

 of the year ; and to those who know but little of these 

 creatures these cages are highly popular, and as this 

 is evidently the aim of the Insectarium I think it 

 must be pronounced successful. — George D. Harvey. 



Boring Sponges. — A recent number of the 

 " Science Record" (a new American scientific journal 

 ■of great ability and promise) has the following : — In the 

 ^seas of both Europe and America, are a group of 

 sponges which possess the power of boring into shells 

 and into limestone. On our coast Cliona sulp/iurea 

 'Causes the rapid disintegration of the dead shells of 

 the molluscs. It excavates tortuous channels in the 

 shells, which soon result in their complete destruction. 

 How these sponges bore is still a mystery. Some 

 have supposed that it was by chemical means, and 

 •some by mechanical agencies. Nassonow has recently 

 attacked the problem again, and describes the 

 process. He is, however, uncertain as to the way in 

 which it is accomplished, though inclined to accept 

 both views. He claims that the spicules take no part 

 in the boring, a view which would appear to be well 

 founded, for he found that the young sponge begins 

 its excavations before any spicules are formed. 



The Reported Scarcity of Butterflies. — 

 I am afraid the increasing dearth of butterflies results, 

 in a great degree, from causes which it would be a 

 •difficult matter for naturalists' societies to interfere 

 with. The raids of collectors do not extend to this 

 side of the Channel, but for some years we have had 

 singularly few butterflies. The red admiral and 

 peacock have become quite scarce, and the common 

 blue is no longer to be seen in fields where I remem- 

 ber it abundant. Two of our more local insects, the 

 ;brown hairstreak and dingy skipper, will probably 

 become extinct in a few years, in consequence of the 

 recent cutting down of the remnant of Killoughram 

 Forest ; a picturesque old wood of oak and birch, the 

 >resort of innumerable butterflies, and in whose glades 

 ■the two last-named species seemed to have established 

 ■their peculiar home. The purple hairstreak, too, 

 though enjoying a more general distribution than its 

 'brown congener, was to be met with in profusion in 

 Killoughram only. I suppose we must now count it 

 as one of our rarer kinds. A very remarkable non- 

 appearance during the present season is that of the 

 marsh fritillary [Aleiitcra Artemis). Of this insect I 

 find it recorded in Mr. Coleman's " British Butter- 



flies," that it has one known locality in Ireland, viz. 

 " Ardrahan Castle, county Galway." A quarter 

 of a mile or so from where I write, there is a little 

 boggy field, where, until the present year, it might 

 have been observed flitting about in quantities among 

 the orchids on any sunny morning of June or in the 

 beginning of July. I first noticed it in 1877, and 

 have since naturally been to the spot many times in 

 each succeeding summer. For no very obvious 

 reason, it had prescribed to itself an area embracing 

 scarcely more than a third part of the field ; so that 

 should this piece of ground ever be drained, or, as 

 seems much more probable, totally overgrown with 

 alders, the marsh fritillary would become extinct, 

 perhaps from here to the county Galway ! In the 

 meantime, having visited us regularly, sometimes before 

 the end of May, for seven successive seasons, it has 

 this year up to the present date (July ist) altogether 

 failed to appear. I should like to know whether it 

 has been at all scarcer than usual in its English haunts. 

 It is five years since I have seen a clouded yellow ; 

 1876 was the only year it was really common in 

 Wexford, but it came out sparingly in the three 

 following summers, and then was seen no more. On 

 the other hand, the painted lady is commoner just 

 now than she has been since 1879. Of course, the 

 specimens are hibernated, which makes their sudden 

 reappearance all the more perplexing. — C. B. Moffat, 

 Ba 11} 'hyla nd, Enn is cor thy . 



Free-Swimming Rotifer. — I cannot accept Mr, 

 Bousfield's statement that I shall find my rotifer 

 described in " Pritchard " under the genus Lepadella, 

 fam. Euchlanidota. In two species of that genus the 

 lorica is depressed ; the lorica of my specimen is com- 

 pressed. The third species is described as having a 

 "lorica oblong, prismatic, obtusely triangular, back 

 crested, denticulated." This description will cer- 

 tainly not fit. Then again the absence of eyes is 

 one characteristic of the genus Lepadella ; in every 

 specimen I examined there was a small, but well- 

 defined eye. This character, however, for reasons 

 which I need not here specify, is not considered by 

 some authorities to be of great value ; but my speci- 

 men had one character to which no such objection 

 can be taken, viz. the lorica being open on the ventral 

 side J this at once shows us that it belongs to the 

 genus in which I placed it. It differs however from 

 every species of Colurus, mentioned in " Pritchard," 

 by its one eye, by its lorica being pointed anteriorly, 

 and by the long, turned-up posterior spines. Since 

 my note appeared, I have received numerous 

 letters from correspondents, referring my rotifer to 

 widely different genera, which goes to prove that the 

 descriptions and figures given of many of the more 

 minute free-swimming forms are very imperfect, and 

 give a student little help towards identifying many 

 of his finds. In another journal, "Microscopical 

 News," I am contributing a series of articles upon 



