HARDWICKE'S SCIENCE- GOSSIP. 



103 



several leaves, and making choice of a suitable one, 

 the vroulcl place that part of her body from whence 

 the egg is about to protrude onto the leaf, and with 

 her hind legs fold the leaf over and around that 

 part iu such a manner as to enable her to receive 

 the egg into the leaf between the two legs,'the body 

 being bent forward for that purpose. As soon as 

 the egg is laid, the body is slightly raised from it, to 

 give room for the further and complete folding of 



egg was enclosed in a single leaf of ^. alsinastrum, 

 and was close to the side of the glass when laid 

 which gave me a good opportunity for observation 

 The eggs are oval in shape and transparent, so that 

 the nucleus of the egg is plainly seen. At first 

 this is quite round, and of a brown colour. In 

 three days it becomes somewhat lengthened. The 

 egg was laid April 17tl), 1873, and the nucleus con- 

 tinued to grow up to April 25th, when the tadpole 



Fig. 74. Earliest stape of free Tadpole, a, claspers; J, fore-leg partly 

 developed; c, circulation of blood ; J, transparent fin ; e, branchiate 

 tufts. 



Fig. 72. Without the dotted lines, shows the growth of 

 Tadpole eight days after the laying of the egg. The arrows 

 indicate the current motion caused by cilia. The dotted 

 lines show the increased growth at the eleventh day. 



it in the leaf, and is then held in that position for 

 about three minutes to insure its firm adhesion to 

 the leaf. The female newt then swims away. 1 

 have sometimes seen her return to the recently-laid 

 egg ; and, as if not satisfied thai all was as it should 

 be, she would take the folded leaf, together with 

 the enclosed egg into her mouth, pressing it gently 

 to make sure it was in a proper and safe position. 

 This I have seen the newt do to several eggs, the 



Fig. "3. Further development of Tadpole, seventeen days 

 after the laying of the eg^. 



laying of which I witnessed. When first I saw her 

 take the egg and leaf into lier mouth, I appre- 

 hended she was going to destroy it ; but not so. 

 One of the eggs that I saw laid and then adjusted 

 with her mouth, I took out from the glass, together 

 with a portion of the plant on which it was fixed, 

 and placed it in a glass cell 1| inch in diameter and 

 i inch in depth, so that at any time it could be 

 placed under the microscope. In this way I was 

 enabled to make the following observations. TTiis 



within presented the appearance as shown in 

 fig. 72. There was no appearance of the branchiaj 

 at that time, but a constant circulation of the fl.uid 

 contained in the egg was perceptible passing in the 

 direction indicated by the arrows (fig. 72) over that 

 part of the tadpole where the branchiae were forming. 

 This circular current is caused by vibratile cilia, 

 and though too fine to be perceived, the action is 

 very plainly seen, and as the branchiae were deve- 

 loped, so the circular motion became more rapid. 

 On April 25th the tadpole in the egg presented the 

 appearance as shown in fig. 72 without the dotted 

 lines. The dotted lines are intended to show the 

 gradual and progressive growth of both the branchiae 

 and the tail, day by day, up to April 28th. It thus 

 gradually increased in size and changed its form 

 until May 4th, when it presented the form as in 

 fig. 73, having at this period a far greater likeness 

 to a fish than a reptile. » ,. 



Fig. 75. Tadpole ot Newt three months old. 



The circulation of the blood through the branchial 

 tufts while still in the egg was plainly seen, forming 

 a pleasing sight ; the tadpole, at intervals, changed 

 its position in the egg by sudden jerks. On 

 May 10th it burst the egg, and escaped into the 

 water (fig. 74). At this early stage the circulation 

 of the blood in the branchial tufts and other parts 

 of the body is plainly seen, forming a beautiful 

 spectacle, and can be witnessed by placing one of 

 the tadpoles in a small shallow cell with just suffi- 

 cient water to allow it to float. The action of the 

 cilia is then very visible, causing a rapid current of 

 water to pass over the branchial tufts in a direction 



