YELLOWBIRD 



0.387 



YELLOWLEGS 



YELLOWBIRD. See AMERICAN GOLDFINCH. 



YEL'LOW FE'VER, a dangerous infectious 

 disease, so called because it causes the skin of 

 its victims to assume a yellow tint. The spe- 

 cific germ which causes it has not been identi- 

 fied, but it is known that it is transmitted by 

 the bite of a mosquito known to scientists as 

 Stegomyia calopus. A full account of the ex- 

 periments which proved the malignancy of this 

 mosquito and the story of the measures 

 adopted to combat it are given in these vol- 

 umes in the article MOSQUITO, pages 3967-3968. 



Yellow fever is a warm-climate malady. It 

 first recognized as a definite disease in 1647 

 in the West India Islands, and since that time 

 has been known in West Africa, South America 

 and in Southern United States. American oc- 

 cupation in Cuba and the Canal Zone has 

 driven it out of those regions, and the disease 

 has also been conquered in New Orleans (see 

 page 4180). Wherever the principles of sani- 

 tary science have been applied, particularly 

 along the line of exterminating the mosquito, 

 yellow fever has become a thing of the past. 



Usually three or four days intervene between 

 the infection and the beginning of an attack. 

 The initial symptoms are frequently weakness, 

 headache and a general feeling of discomfort, 

 but the victim may first have a severe attack of 

 chills. The temperature rises in a few days to 

 105 or more, and lasts for a period of from 

 three to five days. Severe pains occur in the 

 head, limbs and back. Nausea, vomiting and 

 jaundice (spreading over the entire body) are 

 other symptoms. If the case ends fatally the 

 symptoms increase in violence, and the vom- 

 ited matter becomes black, indicating the pres- 

 ence of blood in the stomach. Hemorrhages at 

 the nose and mouth are liable to occur, and at 

 this time the victim becomes delirious. Very 

 bad cases sometimes terminate in death a f< \v 

 hours after the patient is stricken. Persons 

 who recover usually begin to improve at the 

 of the fourth or fifth day, and are well at 

 the end of two or three weeks. Absolute 

 in hod during the entire attack is easen 

 A physician can prescribe measures to take 

 care of the symptoms. C.BJJ. 



YEL' LOW-HAM 'HER, one of the thirty- 

 six names of the genial flicker, or golden- 

 winged woodpecker, the largest and most com- 

 mon woodpecker in . \merica. See FLICKER. 



The title properly belongs to the 

 bunting, one of the most common of the .- 

 birds of Great Britain and many parts of Hi-- 

 Continent. The name yellow-hammer is a cor- 



ruption of the German ammer, meaning bun- 

 ting. The bird has a brilliant plumage of yel- 

 low, varied by dark patches of brown, and 

 tl i.-ky black wings edged with gold. All the 

 summer its short, sweet songs issue from the 

 hedges and low trees, where the birds build 

 their nests. Their eggs are spotted with red, 

 and because of this the inoffensive little bird 

 has been the victim of much persecution. Ac- 

 cording to an old tradition, it flew too near 

 the Cross and its plumage was stained with 

 blood. As a punishment, it was said, the eggs 

 were spotted with red. Because of this super- 

 stition, the bunting has been scorned in many- 

 lands, and its nest has been pillaged and de- 

 stroyed. The bird is often used as food, and 

 in Italy large numbers are raised for the mar- 

 ket. 



YELLOW JACK 'EX, a small species of 

 American wasp, striped black and yellow and 

 notorious for its vicious disposition. It is one 

 of the social wasps and lives in large communi- 

 ties. The nests are built beneath stumps and 

 stones or often in 

 excavations in the 

 open ground. 

 They consist of 

 eight or more 

 horizontal layers 

 of cells, and 

 sometimes con- 

 tain as many as 

 15,000 cells. The 

 underground 

 nests are often 

 larger than a 

 half-bushel bas- 

 ket , and are 

 reached by tun- 

 nels opening into 

 the center of the 

 nr.-t. The outer, papery covering of the yellow 

 jacket's nest is less firm and tough than that 

 made hy the hornets. The life history and 

 habits of the yellow jackets are similar to those 

 of the larger wasps. They feed largely upon 

 the juices of ripe fruit, and cause considerable 

 loss in orchards and market gardens, but com- 

 pensate for this damage by destroying many 

 grubs and blowflies. See WASP. 



YELLOW JASMINE, /cu'min. See GEL- 



8EMIUM. 



YELLOWLEGS, a common American snipe, 

 with black and white markings and long, yel- 

 low legs, found along shores and in marshes and 

 easily decoyed by hunters. It nesta from the 



YELLOW JACKET AND 

 NEST 



