80 . Miscellaneous. 
former visit he was unable to say, as the animal is as transparent 
as the water in which it lives, and may easily escape observation. 
His attention was accidentally directed to its discovery. Along the 
edge of the pond there were numerous linear white bodies, flaccid 
and motionless, which he at first took for fragments of a bleached 
alga. From the uniformity of their size he stooped to examine 
them more closely, when he noticed others in the water, more 
transparent, lying on the sand and occasionally moving suddenly 
and so actively as to send a little spray above the surface. On 
transferring some of these bodies to a vial he detected their nature.- 
Subsequently the water was seen to swarm with the little creatures. 
They are exceedingly sensitive, and quickly die after removal. In 
life they are perfectly transparent and colourless, and move actively 
at intervals with a sort of spasmodic jerk, bending the tail down- 
wards and darting forward. After death they become flaccid, dull, 
and white; and hence the appearance of the multitude of dead ones 
on shore. 
The Sagztta is interesting as being one of those peculiar animals 
which have puzzled naturalists as to its exact relative position. It 
is now usually regarded as the representative of an order of worms 
with the name of Cheetognatha. 
A species, Sagitta elegans, has been described by Prof. Verrill as 
occurring at Wood’s Holl, Vineyard Sound, and Gay Head, on the 
New England coast ; and he refers to a second, undetermined species 
occurring in Vineyard Sound. 
The Sagitta of Atlantic City appears to differ from the former, and 
also from all other described species found elsewhere, and may be 
readily distinguished from them by its greater number of mandibular 
hooks. It may be characterized as follows :— 
Sagitta falerdens. 
Animal transparent, colourless; body compressed, elongated 
fusiform, with two pairs of lateral hemielliptical fins, separated 
by intervals from each other and the broad obcordate caudal fin, 
which is truncated posteriorly. Head obcordate, about as broad 
as it is long. Preoral series of spines, 6 or 7 in each, minute; 
postoral series 18 in each, successively decreasing. Mandibular 
hooks, from 11 to 14 in each series, usually 12, besides an immature 
one, scythe-shaped, yellowish brown in colour. Length about three 
fourths of an inch, width 14 to 2 millim. Head 1 millim.; caudal 
fin 1:5 to 1°75 millim. wide. Mandibular hooks 0-75 millim. long. 
At the same time, as previously, numerous mounds of the Balano- 
glossa aurantiacus were observed. There were also noticed in the 
same pond many projecting tubes of sand, which were found to 
contain Clymena torquata. Further, several specimens of Glycera 
americana were collected. On the shore of the pond in one place 
Donax fossor appeared to have its residence; and among NSolen 
ensis, a Single living Solecurtus gibbus was found,— Proc. Acad. Nat. 
Sci. Philad. April 4, 1882, p. 102. 
