73 



I have already pointed out the features, and proposed a 

 name for this singular subdivision, in a paper published in Silli- 

 man's Journal. I have, since writing that article, discovered 

 one species, in addition to the three mentioned there. They 

 are all anomalous, and differ from each other in many points ; 

 while they agree in the characters which I have assigned. 

 They hibernate in silk tubes, under the bark of trees. 



1. Synemosyna formica. 

 PI. 9, fig. 18. 



Description. Rufous ; cephalothorax very long, contracted 

 in the middle, tapering towards the base, and with two lateral 

 yellowish spots ; abdomen contracted in the middle, also with 

 two lateral yellow spots, each where the contraction appears ; 

 feet slender, varied with yellowish and black, 4. 3. 1. 2., tibia? 

 of the first pair and part of the tarsus black underneath. 

 Male with very large cheliceres ; legs, 4. 1. 3. 2. 



Observations. This spider cannot be placed in the subgenus 

 Myrmecia, of Latreille, as described in the fourth volume of the 

 Ann. des "Sc. Nat., or in Vol. iv. p. 261 of the Regne Animal, 

 [369] for the following reasons ; the eyes are very unequal in 

 size, and not placed in the manner described ; the cheliceres 

 are large only in the males ; and the length of the feet is not 

 the same. It is possible, however, that the insects drawn by 

 Abbot belong to this division ; for, being very small, probably 

 the situation of the eyes may not have been correctly observed. 

 Be this as it may, the subgenus Myrmecia, or Myrmecium, is 

 closely related to this. 



I had seen individuals of this species running on the blades 

 of grass and stems of weeds, long before I distinguished them 

 from ants. They move with agility and can leap, but their 

 habitus is totally different from Attus. They move by a regu- 

 lar progression or regular walk, very different from the halting 

 gait of that subgenus. 



Habitat. North Carolina, Alabama. 



