32 PROTECTION OF PLANTS, 192C-21 



insects — by their wonderful physical adaptation to their surroundings, by their 

 ability to reproduce themselves at enormous rates, by their prodigious appetites, 

 and their power of withstanding, in some form, extremely wide ranges of temper- 

 ature, — show themselves to be man's formidable rivals for the possession of 

 the earth. It has become a commonplace to be able to destroy by a few shots, 

 a great ship which is so far away as to be almost invisible, but man's victories, — 

 even his partial victories, — over insect attacks, may be counted on the fingers 

 of one hand. 



One invertebrate group, the Spiders, stands as man's ally against the in- 

 sects, and, — while as yet scarcely recognized as a friend, — works early and late in 

 building and rebuilding its snares for the common enemy. The other invert- 

 ebrates are of no economic importance, except the Mollusks and Crustaceans, 

 which are eaten by man and those others which furnish food for fishes. The 

 vertebrates may largely be accounted as allies, — the fish destroying enormous 

 numbers of insect larvae ; amphibians and reptiles, living almost entirely on 

 adult forms ; while in the birds we recognize our very best friends, especially 

 qualified to give us both gratification to eye and ear, and much needed assis- 

 tance in restraining the swarming millions of insects. If the inactive toad or 

 frog is worth two dollars per year to the gardener, what indemnity shall we fix 

 for the nuthatch, creeper, and vireo searching our trees from roots to branch tip 

 for eggs, larvae, or winged insect, or the swallow and martin sweeping the galleries 

 of the air and appearing at the nest every ten minutes with a new captive ! 



By glancing over the different groups of birds we may reach a better con- 

 ception of the gratitude we should feel for these our allies, and the support and 

 encouragement we should give them. In arranging birds in groups which show 

 their relationships, we begin with those which make their homes and find food 

 and safety in, or almost in, the water. The first group is that of the Pygopodes 

 or Divers including Grebes, Loons and Auks. These are all fish eaters, although 

 no doubt Grebes eat numbers of insects and larvae in the fishless ponds in which 

 they often raise their broods. 



The second order of birds is that known as Longipennes or Longwinged 

 Swimmers including the Gulls, and Terns. Many of these are insect eaters, 

 especially Franklin's Gull which feeds on the worms, grubs and grasshopper* 

 enemies of our prairie farmers. The Black Tern also deserves its name of Sea 

 Swallow from its habit of hawking over our marshes, and living to some extent 

 on insect food. The Tubinares are haunters of the deep seas, tireless fliers and 

 probably of no economic value. The Fulmars, Shearwaters and Petrels belong 

 to the waters off our Atlantic Coast. The next order — the Steganopodes — 

 includes the swimmers which have all four toes united by webs. These are the 

 Gannets, Cormorants and Pelicans. All of these are fish eaters and some of 

 them have been accused of injuring the salmon fisheries, but intelligent study 



