106 THE NATURALIST’S GUIDE. 
low, “ White-bellied Martin.” Abundant summer resi- 
dent. Arrives from March 31st to April 12th; the first 
of the Swallows in spring, also remaining the latest, de. 
parting about the middle of September. It congregates 
upon the salt marshes during the latter part of August 
and first of September literally by millions ; the air is so 
completely filled with them that it is almost impossible to 
discharge a gun without killing some, Nests in the mar- 
tin-houses, or in holes in buildings. I was extremely in- 
terested when, in company with my friend, Mr. Allen, we 
found a nest containing six eggs, built in the primitive 
manner, in a hole of an old blasted cedar-tree, upon the 
Ipswich Sand-hills. The tree had probably stood there for 
centuries. 
53. Cotyle riparia, Boi. — Bank Swallow. Abun- 
dant summer resident, especially along the coast. Arrives 
from May 13th to 21st; leaves the last week in August. 
Breeds by the thousand in the sandy banks along our 
shore, also in the interior. Both sexes assist in incuba- 
tion. 
54. Progne subis, Bairp.— Purple Martin, “ Black 
Martin.” Common summer resident ; somewhat local in 
its distribution ; very abundant upon Cape Cod, while in 
some places in the interior it is rare. Arrives the last 
week in April; leaves about the last week in August. 
VIREONID.®, — Tre Vrreos. 
55. Vireo olivaceus, Viriti. — Ned-eyed Vireo. Very 
abundant summer resident. Arrives from May 4th to 
19th; leaves about the middle ot September. Nests on 
trees in the woods, where it is always found. 
56. Vireo gilvus, Box. — Warbling Vireo. Common 
summer resident. Arrives from May 8th to 16th; last 
