REPORT ON THE STOMATOPODA. 103 



increased in size and iu uumbers. Tlie sides of the carapace are folded down over the 

 body more than they are in the younger larvae, and the median dorsal spine is relatively 

 shorter. The appendages of the thii'd, fourth, and fifth thoracic somites are represented 

 by buds, as well as the fifth abdominal appendages, and the three last thoracic somites 

 are now longer than those in front. While I obtained a number of specimens of this 

 stage I found only one older one, which moulted, before I had an opportunity to draw it, 

 into the young Lysiosqidlla excavatrix, shown in PI. X. fig. 13, although I was able to 

 make from the moulted skin the drawings of the carapace and telson which are given 

 in figs. 14, 15, and IG, of PI. X. 



Although this larva, the carapace of which was ^ inch long on tlje middle line, 

 including the rostrum, and ^'\j inch wide between the bases of the postero-lateral 

 spines, is many stages older than the one last described, the difi'erences are so very 

 great that I at first doubted whether they could belong to the same series, but the 

 consecutive series of stages in the growth of the closely related larva which is described 

 in the next section furnishes satisfactory proof that this is the case. The antero-lateral 

 and dorsal spines are now very short, although the rostrum and postero-laterals are of 

 about the same relative length as before, and none of the marginal spines were visible 

 with the hand-lens under which the drawings were made, except one in front of the base 

 of each postero-lateral and one in front of this by one-third of the distance to the small 

 antero-lateral. The telson (fig. 16) is now nearly rectangular, a little (^) wider than long, 

 with very long submedian spine, and a nearly transverse but notched posterior border 

 carrying thirty-six small secondary spines with very minute spinules between them. As 

 compared with the submedians the other marginal spines are very small ; the laterals 

 are posterior to the middle line and have each a small spinule internal to the base, 

 and one of the three secondary spines which were present in the younger larva has 

 disappeared, while the second is very small, and the third much smaller than the 

 intermediate. The change which takes place between this .stage and the next, in the 

 shape of the telson, is fully as great as the difl'erence between the telson at this stage and 

 that of the very young larva, as immediately after the moult the young Lysiosquilla has a 

 telson essentially like that of the adult shown in PL X. fig. 8, transverse, and about twice as 

 wide as long, with no secondary spines, and with all six marginal spines on the transverse 

 posterior border, and the submedians united in a single median process, as shown in fig. 13. 



I am inclined to believe that a small Erichthoidina larva, which is occasionally, 

 although very rarely, found on the eastern coast of the United States, is the larva of this 

 species. Faxon has found one of these larvae at Newport, R.I., and he has figured it in 

 pi. viii. figs. II and 12 of his selection from Embryological Monographs.' Through the 

 courtesy of Professor Baird I have also had an opportunity to examine a sketch of another 

 specimen which Professor S. J. Smith obtained at the United States Fi.sh Commission 



' Bull. Miis. Comp. ZooL, vol. ix. 1, 1882. 



