on the Southern Coast of New England. 95 



the channel at Wood's Hole, the southern purple sea-urchin 

 [Echinocidaris punctidata)^ the orange starfish [Crihrella 

 sanguinolenta) , the green starfish, the coral {Astrangia Dance\ 

 and many other interesting species occurred. All the species 

 referred to, excepting the widelj diffused species of Crihrella 

 and Amphipholis^ are either characteristic southern forms or 

 else species that are not yet known except from the region 

 explored. Several species were also obtained in Vineyard 

 Sound which had not previously been found so far northward. 

 Among these the flat sea-urchin with five perforations {Mel- 

 lita pentapord) is especially worthy of mention, as it has 

 hitherto been regarded as peculiar to the Carolinian fauna*. 

 The free-swimming forms taken at the surface in this region 

 were also numerous, and are likewise chiefly southern species ; 

 or if new, they belong to southern types. Among the most in- 

 teresting were : — Salpa Cahotii^ which occurred in vast quan- 

 tities about the 1st of September, and was found in abund- 

 ance off Gay Head, as Avell as in the sound ; a splendid 

 species of Sajyhirina, reflecting brilliant blue and red colours 

 like a fire opal, which occurred mingled with the Salpce ; a 

 new free-swimming crab ; Idotcea rohusta^ Kr. ; innumerable 

 young lobsters, crabs, and shrimps, in the zoea and megalops 

 stages of growth ; numerous jelly-fishes, among which Mne- 

 miopsis Leidyi was perhaps the most abundant ; but a species 

 of Cyanea and Dactylometra qidnquecirra were common, and 

 both frequently gave shelter to several young " butter-fishes" 

 {Poronotus triacanthus) of all sizes, from those just hatched up 

 to two inches or more in length. In some cases twenty or 

 more were found together under one jelly-fish ; they also 

 occurred, in the evening, under Zygodactyla granlandica 

 earlier in the season. The " Portuguese man-of-war" [Phy- 

 salia Arethusa) was met with several times. Two Pteropods 

 not before recorded from the United- States coast were obtained, 

 — one of them {Stiliola^ sp.) living, associated with Salpa\ 

 but of the other [Cavolina tridentata) the shells only were 

 dredged, but in a very fresh condition. 



In the deeper outer channels, as between Gay Head and 

 No Man's Land, and at nearly all points outside of the latter 

 where the water is more than ten fathoms in depth, the fauna 

 is very different from that of the sounds and bays, and closely 

 resembles that of Massachusetts Bay and the coast of Maine. 

 The difference in the temperature of the water is also well 

 marked. The surface temperature, during the latter part of 



* Tins and Lytechinus variegatus were found by the writer, Mr. S. I. 

 Smith, and Prof. J. E. Todd at Great Egg Harbour, N. J., last spring, but 

 they are very rare at that locality. 



