C AL AN DRIN I A CALCAREOUS SPAR. 



6G3 



cntly understood ; that the egg or larva of the 

 insect may at times be observed in the grains during 

 the winter, although in very small quantities; and 

 hence, that corn, purchased in the winter months, can- 

 not be considered as entirely free from the weevil. 



Other species of this genus are scarcely less" destruc- 

 tive than the preceding. One of these (Curculio oryzce 

 Linnaeus), which nearly resembles the C. granarla, 

 but has a yellowish spot on each wing cover, feeds 

 upon grains of rice. A third (Curculio palmarum, 

 Linnaeus), whose size being an inch and a half long, 

 renders it a most formidable enemy, lives in the 

 palms of South America, where its larva; are greedily 

 sought after and devoured by the inhabitants. The 

 same insect, as we are informed by the late Rev. 

 Lansdowri Guilding (in his Memoir upon the insects 

 which attack the sugar cane, for which he was, in 

 1831, honoured by the Society of Arts with the gold 

 Ceres medal), is also injurious to sugar cane plants 

 lately stuck in the ground, to which the females are 

 allured by the juices which are exuded. These they 

 sometimes attack so vigorously, that a fresh planting 

 becomes necessary. They, however, do not seem to 

 deposit their eggs in full grown canes when palms 

 are abundant in the neighbourhood. Another, but 

 smaller species, Calundra sacchari of Guilding, in like 

 manner attacks the cane, but confines itself p.rin- 

 cipally to such plants as have been slightly injured, 

 though it sometimes attacks the more vigorous plants, 

 which it excavates to the very ground. The larva? 

 of these two species, unlike the corn weevils, form 

 very perfect cocoons. 



The only other species which we shall here notice 

 is the Calandra tamarindi, de.-cribed by Mr. Christy in 

 the first number of the Transactions of the Entomo- 

 logical Society, and which was found in a dead state 

 in the interior of the stones of prepared tama- 

 rinds, sometimes amounting to as many as thirty 

 or forty in a single stone. How the insects found 

 their way into the stones is a curious point for 

 inquiry, since the latter exhibited no trace* of punc- 

 ture in the epidermis. Can it be, as Mr. Christy 

 pertinently asks, that the female deposits her egg's in 

 the fruit when very young, or in the germen when in 

 flower? This knowledge, however, can only be 

 obtained by observations made upon the growing 

 plants in the West Indies. 



CALANDRINIA (Humboldt). An ornamental 

 genus of herbaceous plants from South America. 

 Linneean class and order, Dodecandna j\f(u>gi/n>n ; 

 natural order, Portulacea;. Generic character : calyx 

 of two persisting sepals ; corolla of from three to five 

 equal petals ; stamens inserted into the bottom of 

 the petals, in number four to six ; filaments dilated 

 at the base ; anthers two-celled ; style simple ; stigma 

 three-parted ; seed-vessel elliptical, covered by the 

 persisting calyx, one-celled, three-valved ; many- 

 seeded ; placenta central. These rather showy plants 

 have been but lately introduced into British collec- 

 tions, but they flower freely and are much admired. 



CALANTHE (R. Brown). An . orchideoui 

 genus lately introduced from India. Linmean clas 

 and order, Gynandria Diaitdriu ; natural order, Orc/ii- 

 dc(. Generic character : sepals distinct, upper ones 

 erect, laterals declining ; labellum spurred, appended 

 to the column, hairy, three-lobed, middle lobe cleft ; 

 column obovate, turbinate ; anthers behind. This, 

 like all the others of its order, has flowers" of the mosl 

 curious structure, though not so varied in colour as 



some others. They are terrestrial plants, and may 

 )c cultivated like cvmbidium. 



CALATHEA (Meyer). A genus from Brazil, 

 allied to the arrow-root plant. Linmean class and 

 order, Monandria Afonogynia; natural order, Cannes. 

 Generic character: anther attached to a petal-like 

 filament ; style shaped like a petal ; stigma like a 

 cup. Flowers in close heads. The leaves of this 

 plant are curiously striped green and white, hence 

 the specific name Zebrina. It was formerly known 

 by the name of Maranta zebrina. 



CALATHIAN VIOLET is the Gentiana pneumon- 

 anthc of botanists, belonging to a beautiful tribe of 

 herbaceous perennials cultivated in flower gardens. 

 The tuberous roots are used in medicine. 



CALCAREOUS SPAR. This beautiful mineral, 

 which is in fact a crystallised carbonate of lime, occa- 

 sionally combined with other bodies, occurs very 

 abundantly in many parts of the world. The crys- 

 talline masses which are procured in Derbyshire are 

 found in most mineralogical collections. Calcareous 

 spar generally occurs of a white colour, inclining to 

 red and grey. It is also frequently seen of a wax or 

 ochry yellow colour; but the white and grey varieties 

 are usually massive. Us primitive form is a rhom- 

 boid, but imagination can scarcely paint any thing 

 more beautiful than the stalactiiic varieties which are 

 occasionally found in its natural state. It will only be 

 necessary for us to furnish a graphic illustration of 

 one form of this crystalline body. It is copied from a 

 specimen in the British Museum, brought from Der- 

 byshire. 



Calcareous Spar has three characteristic forms, 

 which may be briefly enumerated. The first in 

 which it occurs is an acute double six-sided pyramid ; 

 in the second, it forms an equiangular six-sided prism, 

 including the six-sided table ; and in the third, it 

 forms a rhomboid. 



An interesting geognostic character of calcareous 

 spar is the uniformity of its crystallisations in parti- 

 cular districts. Thus, in the mines of Derbyshire, 

 the acute six-sided pyramid, and its congenerous 

 forms, are the most frequent and abundant ; at 

 Schneeberg, in Saxony, anil in the Upper Hartz, the 

 prevailing forms are the regular six-sided prism and 

 table ; while in the mines of Frevberg, the most 

 frequent forms are the regular six-sided prism, acu- 

 minated with three planes, set on the lateral planes, 

 and the flat double three-sided pyramid. 



The oldest formation of this mineral is that in 

 veins, where it is accompanied with felspar and rock- 

 crystal. It occurs also in beds, along with augite, 

 hornblende, garnet, and magnetic ironstone, and fre- 

 quently in veins in different metalliferous formations 



