HORIZONTAL SNARES AND DOMED ORBS. 



155 



Fig. 146. Tetraguatha extended on a twig. 



continent, are Tetragnatha extensa and T. grallator. The former species 

 has been supposed to be an importation from Europe. It is impossible, of 



course, to determine whether this is so or not, for the species is 

 natha^ so widely distributed, over the greater part of the continent in 



fact, that the probabilities are that its life in North America 

 antedates the period of European communication. My collections and 

 specimens range from Canada, Connecticut, 

 and Massachusetts to Florida, on the east- 

 ern shore ; to Texas on the south and 

 southwest ; and on the Pacific coast as far 

 northward as Vancouver Island, and south- 

 ward to San Diego, at the extreme border 

 of California. Emerton has collected it on 

 the White Mountains of New England and 

 along the seaboard, and Dr. Marx has specimens ranging from Fort Simms, 



_ Labrador, to Florida, and westward and northwest through Kan- 



Distri- 



, , . sas, Alaska, and the Aleutian Islands. As the si^ecies is widely 



distributed throughout the continent of Europe, and is probably 

 found in Asia as well, it is easy to see that it might have been transported 

 without the aid of human ships, simply by the agency of the winds, either 

 from America to Europe, or from Europe to America. The original centre 

 of the species, if one is to suppose an original centre at all, cannot, there- 

 fore, be positively determined. It is a spider of delicate greenish and yel- 

 low colors, and appears to be rather delicately organized, notwithstanding 

 the formidable jaws which characterize it in common with its congeners, 

 and to which its generic name is due. (Fig. 147.) Nevertheless, it has 

 been able to find and hold a habitat amid the most 

 diverse climatic extremes, and in establishing itself has 

 crossed continents, lofty mountain ranges, and oceans. 



Tetragnatha extensa is a spider which when once seen 

 cannot easily be mistaken for another. It well deserves 

 its name of " extensa," or the extended spider, for its 

 abdomen is in the shape of a rather narrow cylinder, is 

 greatly extended, as compared with the cephalothorax, 

 and it has the habit of stretching its front legs forward, 

 its hind legs backward until, together with the long body, 

 the entire spider is drawn out into a straight band and 

 forms a peculiar vision, which the observer is apt to bear 

 colors of Extensa vary a good deal, but for the most 



The abdomen is 



Fig. 147. The jaws and 

 mouth parts of Tet^ 

 ragnatha. 



The 



in mind. 



part the cejjhalothorax is pale white and yellowish. 



delicate yellow, tinted with shades of green, and has a fine branching 



black line running down the middle of the dorsum. The sides are finely 



reticulated, and the under part has a dark band down the middle with 



green on each side. 



