PLANKTON OF THE GULF OF MAINE 
131 
they are lifted by active vertical currents. The glass shrimps (genus Pasipheea) are 
the only decapods regularly planktonic in the Gulf of Maine when adult. 
Pasiplieea 
These shrimps are so much larger (80 to 90 millimeters long when adult) than 
any other crustaceans pelagic in the gulf that even a single specimen is sure to be 
detected in the tow. It is therefore safe to assume that the list presented herewith 
comprises our whole catch, which is not true of smaller organisms easily overlooked 
in the mass of other plankton unless abundantly represented in the catch. 
We towed our first glass shrimps (three in number) in the western basin in a 
haul from 150 meters on August 9, 1913 (station 10088). Since then they have been 
taken there on August 22, 1914; August 31, 1915; March 5, 1920; and April 18, 1920 
(stations 10254, 10307, 20087, and 20115), and likewise at two stations in the deep 
water in the northeastern part of the gulf (March 3, 1920, station 20055, and March 
22, 1920, station 20081) ; once in the southeast corner (April 17, 1920, station 20112), 
and once at the outer edge of the shelf off Cape Sable (March 19, 1920, station 20076). 
So far as I can learn, the only previous records of this genus for the Gulf of 
Maine are as follows: Western Basin, approximate latitude 42° 38', longitude 69° 
38', two specimens dredged in 203 meters in August, 1877; two more near the same 
locality, 256 and 311 meters (dredge), on August 27, 1878 (Smith, 1879) ; others from 
Cape Cod Bay and from off Cape Cod, 25 meters and 212 to 223 meters, respectively 
(Rathbun, 1905). 
These early captures were recorded as Pasiphsea tarda, which has long been 
spoken of as the characteristic northern representative of the genus (Wollebsek, 
1908). Sund (1913), however, has more recently shown that at least three perfectly 
distinct and easily recognizable species have been confounded under this name, 
Smith’s own illustration (S. I. Smith, 1879, pi. 10, fig. 1) showing that in reality 
the early American records were not based on tarda but on the P. multidentata of 
Esmark, which has also proved to be the commonest glass shrimp in Norwegian 
waters. 69 All the recent specimens from within the Gulf of Maine likewise are 
multidentata, a perfectly transparent species, whereas P. tarda is commonly blood 
red. Our records of P. multidentata have been from comparatively deep hauls, 
though not invariably from the deepest stratum in the Gulf (fig. 47) as follows: 
Station 
10088. 
10254. 
10307. 
20055. 
Depth of 
Depth of 
Depth of 
Depth of 
haul in 
water in 
Station 
haul in 
water in 
meters 
meters 
meters 
meters 
146-0 
274 
20076 
200-0 
250 
7.5-0 
20081 
140-0 
206 
225-0 
20087- 
200-0 
255 
230-0 
245 
20112 
200-0 
290 
180-140 
230 
20115 
200-0 
290 
So far as I can learn, Pasiphsea has never been taken on the surface or in 
plankton hauls shoaler than 75 meters in the Gulf of Maine, though it has been 
dredged in as shallow water as 25 meters; hence, it is clearly bathypelagic in the 
69 The several species are easily separable by the form of the rostrum, which is high and coniform in multidentata. For details 
I refer the reader to Sund (1913). 
