180 
MARSH TERN. 
after a kind- of large black spider, plenty in such places. This 
spider can travel under water, as well as above, and, during 
summer at least, seems to constitute the principal food of the 
present tern. In several which I opened, the stomach was 
crammed with a mass of these spiders alone ; these they fre- 
quently pick up from the pools, as well as from the grass, 
dashing down on them in the manner of their tribe. Their 
voice is sharper and stronger than that of the common tern ; 
the bill is differently formed, being shorter, more rounded 
above, and thicker ; the tail is also much shorter, and less 
forked. They do not associate with others, but keep in small 
parties by themselves. 
The marsh tern is fourteen inches in length, and thirty-four 
cimens he had received from the United States and Brazil differed in nothing 
from his south Europeans. Even as respects the discrepance of S. Anglican 
Mont., his reasons resting upon the slight difference of an unpublished drawing 
of Wilson respecting measurements of parts, to which Wilson did not attach 
great importance, were by no means conclusive. In fact, these measurements 
are incorrect, with the exception of the tarsus, which corresponds within a trifle 
of the bird. The bill is two and one-eighth inches to the corners of the mouth, 
and about one and one-half inches to the feathers of the forehead ; thus bearing 
more in favour of Mr Ord’s argument, that it is not the Anglica, Mont., than he 
himself supposed ; but proving that it is no other than S. Anglica, Temm., {meri- 
dionalis, Brehm,) to which, as above stated, Wilson’s name of aranea must be 
exclusively applied. 
“ The principal character we should assign for a ready distinction between 
these two closely related species, (in addition to the shorter, thicker, less com- 
pressed, and straighter bill, with its edges turned inwards in Anglica,) consists 
in the tarsus, which in aranea (owing to its shortness, and the extraordinary 
length of the nail) is of the same length as the middle toe, including the nail, 
whilst in Anglica it is nearly twice the length, (owing to its superior length, and 
the shortness of the nail.) The membranes of our bird are also much more scal- 
loped. The habits of the two species are very different. The S. Anglica, con- 
fined to the sea-shores, feeds almost exclusively on strand, birds,* and their eggs, 
sometimes on fishes ; whilst the S. aranea, generally found on marshes, feeds ex- 
clusively on insects.” 
Bonaparte, and the authors of the Northern Zoology, have mentioned the fol- 
lowing species as also found in North America : — 
1. S. cyana. Lath. — Inhabiting the tropical seas of America; common on 
the coasts of the Southern States. 
* Is this correct ? Does this tern kill other sea-fowl, and plunder their nests ? — Ed. 
