38 



HARD WICKE' S SCIENCE- G O SSIP. 



would furnish other examples. The umbelliferous 

 order, with its somewhat monotonous flowers, contents 

 itself with the simple plan of using its two-lobed 

 fleshy disk as a nectary on which the honey lies 

 fully exposed, and a contrast to this method is 

 furnished by such flowers as Pinks, Honeysuckle, etc., 

 which secrete their honey at the base of a long 

 narrow tube where it can only be reached by bees 

 and butterflies. Whether, however, the nectar be 

 exposed or concealed, the nectary is rarely, if ever, 

 represented by an independent organ, but one or 

 other of the normal organs of the flower is modified 

 to form it. It will perhaps be convenient to classify 

 the following examples according to the part that is 

 adapted to form the nectary, but such a classification 

 cannot be rigidly adhered to, since frequently two 

 different organs take part in its formation. 



Sepaline Nectaries. 



To begin with the outer whorls of the flower — a 

 sepaline nectary frequently takes the form of a spur, 

 which may be either a simple receptacle or may 

 itself distil honey by means of special cells or 

 glands at its tip. This latter kind of nectary may be 

 seen in a species of Tropceolum, called in the north 

 the Flame-flower, in the garden Nasturtium, and Im- 

 patiens (Figs. 20, 21) for in these three flowers the 

 spur is formed by the union of two or more sepals, 

 and is both the honey-maker and the honey-storer. 

 In some of the Crucifers such as the common rock 

 Arabis of our gardens (Fig. 22), two of the sepals are 

 pouch-like and hold the honey distilled by the staminal 

 glands, and in the Lime blossom the sweets that 

 make the tree "a summer home of murmurous 

 wings " are offered to its guests in the hollowed 

 sepals of the flower. The functions of the curiously 

 concealed spur of the Pelargonium are not equally 

 clear, but it probably produces the honey that 

 fills it, and which is only accessible by means 

 of an elongated aperture behind the stamens and 

 pistil. It seems specially adapted for bees and 

 moths. In the Euphorbias, too, one cannot but 

 admire the utilization of what was originally a 

 calyx, or part of one, for the formation of most 

 charming nectaries ; for what are the functions of the 

 involucral glands that surround the odd little flowers 

 of Euphorbia peplus and its relatives, if not to distil 

 and display honey ? Coronilla varia (Fig. 29) secretes 

 its nectar upon the outside of the calyx. Curious to 

 relate, the honey is sought for in the ordinary way, 

 for humble-bees and others alight upon the flower as 

 on any other pea-flower, and passing the proboscis 

 through the open space left by the long narrow 

 claws of the standard and alae, suck the honey 

 from the calyx. The flowers being gathered into a 

 compact head would be an additional protection in 

 case the honey should be sought for in an improper 

 manner. 



Petaline Nectaries. 



The so-called "spur " is sometimes formed by the 

 petals, the Columbine being a flower that has 

 fashioned its five petals into as many funnel-shaped 

 vessels, tapering into long curved tips for the distilla- 

 tion of honey. The spur in the Violas (Fig. 26) is also 

 petaline, but it is only a receptacle. An instance of a 

 petaline nectary is afforded by the long slender spur 

 of Habcnaria bifolia, which is fertilized by nocturnal 

 moths. But although the spur is a favourite idea for 

 a nectary, it is by no means the only idea for those 

 flowers who elect to use their petals for the purpose. 

 In Eranthis and Hellebore we see them transformed 

 into cups for holding nectar, and although in one 

 sense the long tube in the honeysuckle- and similar 

 flowers cannot be designated a nectary, in another 

 sense it deserves the name by right of the stores of 

 honey it enables the flower to accumulate, and by its 

 length, which renders them accessible only to the 

 moths and butterflies, to whom it is specially 

 adapted. In the Lily tribe we have another kind of 

 nectary, very curious and interesting. It is a sort of 

 tube with thick raised borders edged by papilla;, and 

 occupies the centre of each of the perianth segments. 

 A groove leads up to it and helps to direct the tongue 

 of such insects as the hawk-moth, to whom alone the 

 honey is accessible, and who in obtaining it must cling 

 to the centre of the flower and thus effect fertilization. 

 The drawing (Fig. 27) was made from a common 

 orange lily. The honey is secreted by the base of 

 ,the ovary. The three species of Nemophila grown 

 in gardens have extremely pretty petaline nectaries ; 

 the idea in each is the same, but differently worked 

 out. Those of N. maculata (Fig. 28), seen from above, 

 have the appearance of little pockets fringed with 

 long hairs, and it is only by inserting the proboscis 

 into the cavity that the honey can be reached, as it is 

 secreted by a ring at the base of the ovary. All the 

 Nemophilas are rich in honey and are greatly visited 

 by bees. The modification of the petals in Nigella 

 (Fig. 30) is very curious, the cavities that hold the 

 honey being closed by a sort of lid that can only be 

 raised by an insect large enough to fertilize the flower. 

 In the common Monkshood two of the ; petals are 

 transformed into long claws hooded at the tip, which 

 secrete honey in their innermost recesses, a groove in 

 the- claw serving as a guide to the insect's proboscis. 

 ( To be continued.') 



DICRANURA VINULA— THE PUSS MOTH. 



HAVING been brought much into contact with 

 this insect, I propose to give a short account 

 of its life-history, which may prove interesting and 

 instructive to those who have not had similar facilities 

 of observing it in a state of nature ; more especially 

 as the life-history of this species applies more or less 



