9 S 



HARDWICKE'S SCIENCE-GOSSIP. 



made, colour being affected by the same cause, 

 towards the base generally showing pink or golden, 

 and nearer the harder apex, blue and purple tints. 



Some species have hollow spines ; such specimens 

 are deeply furrowed longitudinally on the outside, 

 and are generally too large to make perfectly circular 

 sections to fall within a microscopic "field " of view, 

 but delicately cut and ground ; segments of such slices 

 display such remarkable elegance and neatness of 

 design, that when carefully illuminated, and the 

 configuration of the parts studied, they at once 

 impress the mind with their adaptability to purposes 

 of artistic decoration. It is possible no class of 

 microscopical presentations can be more suggestive 

 to the designer of geometrical patterns, and under 

 various conditions of light they are materially altered 

 in appearance. Many parts with transmitted light 

 show configuration, and but slight colour or sub- 

 stance ; under the radiation of dark ground illumina- 

 tion they become totally different, and flash out 

 exquisite translucent pearly lustres. With the polari- 

 scope, especially when the cutting is carefully selected 

 for extreme thinness, but yet preserving the denser 

 parts intact, the beauty is incomparable. Even 

 mounted as purely opaque objects, under the radiance 

 of the side speculum, porcellaneous specimens show a 

 rare delicacy. 



A minute examination of one of these sections 

 recalls the rings and medullary rays of the stem of an 

 exogenous tree, and their number and position (as in 

 the tree) depends on the age of the spine and the 

 part from which it is cut. In the centre is an open 

 network slightly divergent, at intervals zones of 

 larger deposits, calcareous tracery intervening, the 

 whole cut up by equidistant structural radiations ; 

 illuminated with the paraboloid, what appear to 

 be the larger "spaces," as distinguished from the 

 general intersections, are seen of uniform substance 

 and colour. A spine may be defined as a fluted spur 

 of connective hard pellucid tissue, with interspaces 

 filled with solid glass. Spines of the British Echini 

 have no concentric rings, it is supposed in con- 

 sequence of periodical shedding, while in tropical 

 species in the course of growth, layers are added. A 

 crushed spine resolves itself into glass-like particles, 

 transparent and brittle. A power of repairing 

 fracture and injury has been observed, the vitality 

 of the spine and its increase in size is maintained 

 through a connective tissue at the base, and although 

 the internal structure is apparently unprovided with 

 vessels, reparation takes place, as long as the animal 

 be living and the injured spine attached ; many 

 sections, especially when cut through the length, 

 often reveal such interferences of regularity, obviously 

 the result of injury, and recuperative power. 



An attempt was made by the writer to depict, in the 

 second volume of Coles' "Microscopical Studies" 

 (Methods of Research) one of these sections to 

 illustrate appearances under four different modes of 



illumination. The difficulty in preserving delicate 

 line, with painting effects of colour bathed in light ; 

 supplemented by the more limited resources of even 

 the best chromo-lithographer (a condition of things 

 seen in the present subject) reduces such drawings, 

 when printed, to mere semblances of the reality ; 

 but they offer, at least, sufficient inducement to 

 direct attention to the general elegance found in 

 these most popular of microscopical objects. 

 Crouch End. 



THE VIOLET. 



BUY my sweet violet, a penny a bunch ! is one of 

 the familiar cries we hear every morning at 

 this time of year (spring) as we hasten to our 

 respective callings in London (and no doubt in other 

 cities as well). It is a most refreshing sight, to any 

 person who has the least spark of the love of nature, 

 to look at the beautiful baskets of button-hole 

 bouquets which meet our eyes in the different streets, 

 but more particularly in the neighbourhood of the 

 Bank of England and Royal Exchange. The city 

 clerk on his way to his office, purchases a bunch of 

 violets — places them on his desk, surrounded with his 

 day-books, ledgers, and all the paraphernalia of a 

 mercantile house : perhaps once or twice during the 

 day, while his mind is engaged on the routine of his 

 daily duties, the delicious perfume from his morning 

 purchase causes him for a few moments to look up at 

 these emblems of modesty and innocence, and awakens 

 a train of thought of the days of his childhood, when 

 he and his companions hunted for the fragrant flower 

 among the green fields and hedgerows in the early 

 spring. 



But time flies ; work must be finished ; no leisure 

 for such meditations ; still those few moments have 

 not been spent in vain : his brain has been rested by a 

 change of thought, and he is enabled to go on with 

 his work with fresh energy and vigour. Thanks to 

 the little violet. This flower was held in high estima- 

 tion by the ancient Greeks. A golden violet was 

 offered as a prize in their floral games, and we are 

 told in their fables that la, the daughter of Atlas, 

 fleeing into a wood from the pursuit of Apollo, was 

 through the power of Diana changed into a violet, 

 which still retains the bashful timidity of the nymph, 

 by partly concealing itself from the gaze of Phcebus in 

 its foliage. The Greek name for this flower was v lov, 

 said to have been given it because Iov the daughter of 

 Inarchus, whom Jupiter transformed into a heifer, fed 

 upon violets, or, as some mycologists state, sprung 

 from her breath. The Athenians, we know from the 

 writing of Anacharsis, had beautiful gardens attached 

 to their country houses, in which they cultivated the 

 narcissus, hyacinth, iris, and violets of different colours, 

 likewise roses of various kinds. All these flowers were 



