JS. Woodward — On Fossil Crustacea. 523 



[Dr Packai'd, when contrasting (in his work on Larval Limulus) the 

 Mekostomata with Trilobita, by an inadvertence, calls the Meta- 

 stome the " Hypostome," and contrasts it with the Hypostome in 

 Trilobites, in which no lower lip exists.] 



Eeferring to the habits of the Pterygoti, Prof. Owen considers 

 they were those of burro wers, like the Limuli; but their bodies and 

 broad swimming feet seem eminently fitted for natation. On the 

 other hand, he thinks Limulus could not walk well, but only crawl 

 and burrow. We have frequently seen them alive in the Aquaria at 

 the Zoological Gardens, and they walked with very considerable ease 

 and activity on the tips of their toes. They are, however, true 

 burrowers by habit. 



Prof. Owen is willing to accept the theory of the development 

 of the Merostomata from a typical and common life-form, but by 

 "secondary causes or laws," not by Natural Selection, (p. 501, op. cit.) 



Several additions have been made to the Carboniferous Phyllopods, 

 the species of which I have described in conjunction with my friend 

 Mr. Kobert Etheridge, junior (of the Geological Survey of Scotland). 

 (Some notice of these is given more in detail in a separate paper, 

 see page 482.) 



Of Cretaceous forms I have examined several new species, among 

 which are — Three examples of the carapace of a small Gault crus- 

 tacean from Folkestone (near to Dianlax Garteri from the Cambridge 

 Greensand), which I have named D. feliceps. Two small forms 

 of ScyUarklia (a genus hitherto only known in the Eocene Tertiary) 

 — Scyllaridia Gardneri, sp. nov., and Scyllaridia punctata, sp. nov. 

 A small Grangon (?) of doubtful determination, with two delicately 

 serrated lines on the anterior half of the carapace in front of the 

 nuchal furrow, the hinder part armed with very minute spines, 

 the surface of the carapace being ornamented with very minute and. 

 scattered serrations, the carapace, hands, and detached body segments 

 of which are all of a glistening black enamel. I have named this 

 Mesocrangon atra. These specimens are principally from the col- 

 lection of J. Starkie Gai'dner, Esq., F.G.S., who has kindly placed 

 them at my disposal, with others for examination. 



Fifteen years ago Mr. Charles Gould, F.G.S,, described ^ a very imper- 

 fectly preserved carapace of a small crustacean under the name of 

 Mithracites vectensis, from the Greensand, Atherfield, Isle of Wight. I 

 lately obtained six specimens from the same locality, which, upon com- 

 parison, I found to agree (so far as the figure and description enabled 

 me to determine) with Gould's Mithracites ; but when I compared 

 the specimens with the recent Mithrax, I failed to discover the 

 analogy, although the specimens since obtained appear to offer a 

 decided affinity with Hyas. The discovery of these additional 

 examples will necessitate the reconsideration and redescription of 

 the genus Mitliracites. Fortunately the abdomens of both male and 



British Association Reports, Edinburgh, August, 1871, p. 53, and Geol. Mag., 1871, 

 Vol. VIII. pp. 521-624. 



1 See Quart. Journ. Geol, Soc, 1859, vol. xv. p. 237. See also Prof. Bell's Men., 

 part 2, Pal. Sue., 1862 ; Crustacea of the Gault and Greensand, p. 1, pi. 1, tigs. 

 2 and 3. 



