PECKHAM. 



[Vol. 1, 



Fig. 2. — Ariamnes attenuata (from Camljridge). 



Similar in many respects to the Argyrodes group are the 

 Tetragnathina3. These spiders are all slender, and, whenever 

 they are at rest, keep their legs extended in a line with the 

 body. Their usual position is on a branch at one side of 



the web. Their col- 

 oring runs through 

 the shades of brown, 

 yellow and green, 

 and they are frequently mottled or lined with black or white. 

 Mr. Atkinson speaks of a Tetragnatha (pi'obably grallator) which 

 mimics elongated, dark blotches on grass stems ; he says : "I 

 have often seen them, when frightened, leave the web and, cling- 

 ing to a grass-stem, place their bodies close to the stem, stretch- 

 ing the anterior legs above and the posterior ones below. The 

 body being dark and the legs green . the spider was well 

 protected." * 



In some species of Tetragnatha, as in Argyrodes, the tip of 

 the abdomen is elongated and turned upwards. 



We come now to a large and interesting class in genus 

 Epeira. I refer to those species, mostly nocturnal, which are 

 protected during the day, not by hiding in crevices nor in any 

 way actually getting out of sight, but by the close resemblance 

 which they bear to the bark of the trees to which they cling. 

 This resemblance is brought about in two ways ; through their 

 color, which is like that of wood or lichens, and through their 



tuberculated and rugose 

 forms, which resemble rough 

 bark. 



One of the most remarka- 

 ble of these forms is C. mitra- 

 lis, a Madagascar species, 

 which, looked at in profile, 

 probably resembles a woody 

 knot. The abdomen is divided into two divergent cones 

 (fig. 3). The entire upper surface of the body is covered 



*I quote from some manuscript notes whicb Mr. Atkinson lias kindly allowed 

 me to make use of. 



Fig. 3.— Cserostris mitralis (from Vinson). 



