146 



HARD WICKE'S SCIENCE- G OS SIP. 



rarely found in other calcareous organised deposits ; 

 a series of tubuli will be seen permeating through 

 cancellated walls. This tubular development obviously 

 affords strength against external pressures, and 

 although mere conjecture is rarely reconcileable with 

 scientific accuracy, it seems at least an instance of 

 the application of the method of obtaining the 

 greatest strength in the least compass, an idea 

 supported by deeper investigation, as under a power 

 of 70 diameters, the tubular streaks running through 

 the "supports" to the edge of the inner surface, 

 represented in the illustration by waved white lines are 

 ound to be not solid or homogeneous, but so 

 beautifully interlocked, that the whole may possibly 

 possess a certain amount of "play" conducing to 

 power of resistance and expansion ; in a thin section, 

 each piece, with its aperture, may with care be 

 accurately separated. 



Although space is somewhat limited, a word 

 may be said of the " cirri " of the barnacle, the long 

 slender incurved fringes of filaments, a living meshed 

 net, a combination of barbed tentacles, a perfection 

 of arrangement, and, according to the dictum of a 

 great authority, composed of "about five hundred 

 distinct articulations." The sensibility of these 

 tendril-like organs must be most exalted, and thus, 

 the barnacle traps and sifts its food, as the vessel 

 sweeps through the waters. 



The parent cirriped is a fixture, but its progeny 

 are free swimming atoms, not unlike Cypris, one of 

 the minute entomostracans of the ponds, except that 

 in this early larval locomotive stage they keep 

 together in shoals. Under magnification they are 

 most comely and quaint objects. In one of Mr. 

 Gosse's sea-side books is a plate of a pair of these 

 creatures drawn and tinted with extreme elegance. 

 No one who has seen a young cirriped, swirling about, 

 with its compact form and apparently completed 

 organisation, would conceive that it emanated from a 

 parent so dissimilar in form and habits, or that it 

 would eventually subdue its incessant activity and 

 become an "acorn shell" fixed once for all, and 

 wedged in by the pressure of surrounding neighbours. 



Barnacles do not thrive in aquaria, they require 

 the incessant rush and motion of water added to an 

 abundance of microscopic forms of food. Small rock 

 specimens will endure a few days' captivity, when the 

 movements of the cirri may be watched, and attrac- 

 tive microscopical preparations afterwards made of 

 the various parts. 



Crouch End. 



CHARA v. NlTELLA.— Last year a chara (probably 

 foetida) was found within live miles of Tunbridge 

 in a pond by the roadside at Hadlow. If C. J. Bohnso 

 sends his address to me, I would point out the 

 locality.— F. W. E. Skrivell, Hope Cottage, ITadlow, 

 Tunbridge. 



NOTES ON LEPIDOPTEROUS PUPyE. 

 By Albert H. Waters, B.A. Cantab. 



THE situations in which the pupae of lepidoptera 

 occur are many and varied. The common 

 Pieridse and Vanessidae are very partial to the under- 

 side of the coping stones of walls, and some moths — 

 as the vapourer [Orgyia anliqua) — have the same 

 preference also. 



The pupa of the swallow-tailed butterfly {Fapilio 

 Machaoti) is attached to the sedge ; that of the 

 speckled wood (Satyrus sEgeria) to the lower parts of 

 grass stems, the pupa of Satyrus Semele is buried in 

 the earth, and that of Satyrus Hyperanthus is also 

 contained in a little cavity on the surface of the 

 ground. Canonympha Pamphilus too pupates close 

 to the ground on the lowermost part of the grass 

 stems, and Thecla quercus chooses similar situations. 

 The pupa of Thecla betuhv is attached to the under 

 side of blackthorn leaves, and those of the blue butter- 

 flies to the stems of the plants on which the larvae 

 feed. The reed tussock-moth {Orgyia cceuoso), spins 

 its cocoon on the stems of Arundo phragmites, the 

 drinker (Odonestis potatorid) attaches itself to the 

 grass stems ; the rare Aspilates citraria encloses its 

 variegated chrysalis in a slight cocoon among the 

 leaves of Daucus Carota and Lotus corniculatus. 

 Emmelesia albulata pupates in the domicile it lived in 

 throughout its caterpillar life, and which it formed by 

 spinning together the leaves of Rkinanthus crisfa- 

 galli. The prettily coloured eupithecia pupae are 

 mostly buried in the earth, and the green chrysalis of 

 Thera junipcrata is suspended to the twigs of the 

 juniper bushes. 



By digging at the foot of willow-trees in October 

 and the four following months, we are pretty sure to 

 turn up the pupae of Taniocampa instabilis in large 

 numbers among the loose sods, and just beneath them 

 we may possibly find the slightly-spun cocoon of 

 Ptilodontis palpi na, and deeper down in the ground 

 the red brown glossy chrysalis of the eyed hawk-moth 

 (Stncriuthus ocellatus). 



Among the fallen leaves at the foot of oak-trees 

 we may come across the pupa of Sclenia illuslraria, 

 and we may also find it at the foot of birch-trees ; the 

 cocoon in which it is enclosed is a very slight one. 

 If we pull the loose sods to pieces when we commence 

 digging at the foot of the oak-trees, we are pretty 

 sure to find abundance of chrysalides of Taniocampa 

 stabilis, and may expect to meet with those of Tcenio- 

 campa munda. It is also at the foot of oak-trees 

 that entomologists living in its localities may dig for 

 the rare Nyssia hispidaria on the chance of turning it 

 up. Among other pupae to be dug for under oaks, 

 mention may be made oiNotodonta trepida, N. ckaonia, 

 and N. dodoncea. When the roots of the oak-trees 

 are covered by an interlacing growth of brambles it 

 is advisable to look out for the cocoon of Cymatophora 

 ridens anions? 1, the dried leaves and fragments of wood. 



