128 MR. NEWPORT ON THE ORGANS OF REPRODUCTION, 



eighteenth, was now almost as much developed as the preceding ones, and the white 

 germinal membrane, extended from it, showed the formation below it of six new seg- 

 ments. In this state the young animal lay coiled up awaiting its change. 



On the sixty-third day the animal again changed its skin, and entered its sixth period 

 of development. It then had acquired twenty-seven segments to its body, which had 

 greatly increased in size, and was of a brown colour. It had six distinct ocelli on 

 each side of the head, and all the segments, to the eighteenth inclusive, were furnished 

 with legs, of which it had now fifty-eight. Six additional new segments had also been 

 developed to its body, as in the preceding changes, anterior to the penultimate seg- 

 ment ; and the germinal membrane behind them (i) was still in further course of 

 development, the penultimate segment still remaining unchanged. The six segments 

 from which legs had now been developed had also the foramina repugnatoria marked 

 with small spots, while the spots on the preceding six had become larger and darker 

 in colour. The chief difference now consisted in the appearance of the thorax, which 

 is of a lighter colour than the rest of the body. The animal may now be regarded 

 as having acquired all the essential parts of its body. Time and circumstances pre- 

 vented me from following its transformations still further ; but sufficient, I trust, has 

 already been observed to claim from naturalists a little more attention to the remark- 

 able series of phenomena connected with its growth, and to add to the importance 

 of watching the development of this greatly neglected, but most singular group of 

 animals. 



Recapitulation and Conclusions. 



The conclusions to which the facts detailed in this paper seem to lead, are, I think, 

 as interesting to the zoologist, in reference to the situation which this remarkable 

 class, the Myriapoda, ought to occupy in the arrangement of animals, as to the com- 

 parative anatomist, and physiological inquirer. The evident conformity to one type 

 of the organs of reproduction in the two sexes, is in accordance with the views now 

 advocated by the best anatomists. It has been seen that the lulidae, in some parts of 

 their organization, as in the organs of reproduction, approach in their internal struc- 

 ture to the true insect, in maintaining, although in a simple state, a perfect form of 

 development ; while, in the external parts of the same organs, as in the double outlets 

 of the female, and double organs of intromission of the male, they again recede to 

 the type of those in which these organs exist in one of the lowest forms of develop- 

 ment. 



The structure of the ovum in lulus approximates to that of the higher classes, and 

 is in accordance with the observations of Wagner, Bischoff, and of Dr. Martin Barry, 

 whose invaluable researches on this subject have so recently enriched the Transac- 

 tions of the Royal Society. The same reasons that induced this last inquirer to ad- 

 vocate the existence of the memhrana vitelli and chorion in the earlier stages of the 

 ovum of higher animals, have also led me to believe in its existence in these lower 



