HARDWICKE" S SCIENCE-GOSSIP. 



33 



25. All. macrurus, Friend, — — 2 -. Distribu- 

 J ' 20 : 21 



tion. — Malahide, Ireland. 



I omit all allusion to aliens imported with soil 



from abroad, as well as varieties (of which many 



might be created) and doubtful species which need 



confirmation. The consignments which reach me from 



various places week by week give promise of new 



species yet to be recorded, and I should be delighted 



to receive material from the Isle of Man, the Scilly, 



Channel, Orkney, and Shetland Isles, the Highlands 



of Scotland, and any other unworked part of the 



kingdom to which this paper may go. Worms may 



be sent in tin boxeS, lightly packed with soft moss, 



when they will arrive fresh and clean for immediate 



identification or study. My address is 4, The Grove, 



Idle, Bradford. 



A FEW FURTHER NOTES ON EGGS. 

 By P. L. Simmonds, F.L.S. 



THE majority of the Vertebrata are oviparous 

 animals producing perfect eggs, which contain 

 all the material necessary for the development of the 

 embryo. Of the five classes, the first four are 

 oviparous ; namely, Pisces, Batrachia, Reptilia, and 

 Aves. 



The eggs of fishes is too wide a subject to enter 

 upon, but they are much utilised even as food for 

 the human race, in cod and other roes, and in 

 •caviare. 



Professor Peters has lately described the mode of 

 •deposit of its eggs by a tree-frog (Polypedates) from 

 tropical Western Africa. This species deposits its 

 eggs, as is usual among Batrachians, in a mass of 

 albuminous jelly, but instead of placing this in the 

 water, it attaches it to the leaves of trees which border 

 the shore and overhang a waterhole or pond. Here 

 the albumen speedily dries, forming a horny or glazed 

 coating of the leaf, enclosing the unimpregnated eggs 

 in a strong envelope. Upon the advent of the rainy 

 reason, the albumen is softened, and with the eggs is 

 washed into the pool below, now filled with water. 

 Here the male frog finds the masses, and occupies 

 himself with their impregnation. 



Frogs and toads lay numbers of small eggs. They 

 are dropped in the water like fish spawn, in long 

 clusters or strings. The Surinam toad {Pipa) carries 

 her eggs soldered together like a honeycomb on her 

 back. The Aliphes carries them between its legs 

 rolled up in a bunch. 



Among reptiles the eggs exhibit great variety. 

 The eggs of alligators are elongated and almost 

 cylindrical, evenly rounded at both ends, and about 

 the size of an ordinary duck's egg. The eggs of the 

 sea turtle are as large as a small apple, rounded, and 

 have a flexible shell. Those of the snapping turtle 

 (Chelydra serpentina) are much smaller, but also 



rounded. Those of the terrapins (Clemmys, and 

 other genera) are oblong, as also are those of lizards. 

 In the common black and yellow dotted American 

 fresh-water terrapins, and in the painted terrapin, the 

 eggs require four years of growth before they are laid. 

 Take a seven-year-old turtle of this kind ; it will 

 contain only very small eggs, all of uniform size. 

 An eight-year-old tortoise of the same kind will 

 have two sets of eggs, one larger and one smaller. 

 One of nine years will have three sets, the oldest set 

 being the size of a small pea. A tortoise of ten 

 years will have four sets of eggs, and in that year she 

 will lay for the first time, and give birth to the most 

 mature set. 



The scaly reptiles — that is, turtles, lizards, and 

 serpents — bring forth eggs similar to those of birds. 

 They arise in the ovary in a similar way, and produce 

 by successive growth yolks of a similar bulk, as do 

 the birds. While, however, all these eggs are 

 surrounded with a shell after fecundation, the egg is 

 not necessarily laid, as in birds, in order to bring 

 forth the new being. The bird brings forth its young 

 by incubation, sitting upon the eggs, and transmitting 

 to them by its own warmth, the temperature needed 

 for their final development. For the egg of the 

 reptile, that temperature is usually derived from 

 surrounding conditions. It is true that a few kinds 

 of reptiles, the python for instance, sit upon their 

 eggs, and transmit to them a higher temperature from 

 their body ; but this is not usually the case. 



The eggs of the Australian lace-lizard (Hydrosaurits 

 varius) are large, covered with a tough leathery 

 membrane. They deposit some ten or fifteen. 

 The carpet snake of Australia (Morelia variegata) 

 produces a large number of eggs, from twenty to 

 thirty. The diamond snake (Morelia spilotes) deposits 

 thirty or more eggs. The ringed snake (Natrix 

 torquata, Ray) produces fifteen or twenty eggs, which 

 are covered with membrane resembling parchment, 

 and they are agglutinated together in a chain-like 

 necklace. Snake's eggs are oblong and sometimes 

 cylindrical in shape. 



Brown, in his work on Guiana speaking of the 

 iguana, says : " One of these reptiles, captured at its 

 burrow, when killed and cut for cooking, was found 

 to contain ten eggs, of an elliptical form, shell-less 

 and midway in size between a pigeon und a hen's 

 egg. These are good eating, when boiled for about 

 five minutes, and then allowed to get quite cold. 

 They then require some manipulation. A hole is 

 made in one end of the skin, and the albuminous 

 part, which never coagulates, is squeezed out. Then 

 the skin is stripped off, and the semi-hardened yolk, 

 of the consistency of butter, is eaten with salt." 



In the Mollusca we find great variety in form 

 among the eggs. They are sometimes, as in the 

 land-snails, laid separately, each enclosed in a shell 

 of variable consistence; but in most cases they are 

 agglutinated together in a mass, which sometimes 



