461 



the female has no tooth at the base, and in the male's mandibles 

 there is neither a protuberance nor a tooth before the spine on the 

 upper side. Tetragnatha pinicola is a very .small, pretty species , 

 its sternum is black with a fine yellow longitudinal stripe; the la- 

 teral and centre eyes of the two rows are equally distant from each 

 other, the male's mandibles are directed downwards, the spine on the 

 upper side is not cloven at the apex, and in front of it there is 

 neither a protuberance nor a tooth, and the claw on the female's man- 

 dibles has no tooth at the base. — Tetragnatha obtusa has a brown- 

 ish yellow sternum with a shade of black, the centre eyes of the 

 two rows are more distant from each other than are the lateral eyes. 

 The abdomen on the upper side is ornamented with a darker leaf- 

 like patch. On the tibiae of the first pair there are longer spines in 

 a greater number (whereas in T. pinicola only few spines are ob- 

 served, or there are none at all); in front of the spine on the upper 

 side of the male's mandibles there is a conspicuous sharp tooth; the 

 female's abdomen is short and thick and is highest arched towards 

 the base of its length, and looks almost triangular, when viewed 

 from the side — Tetragnatha pinicola and obtusa I have constantly 

 observed only in dry dark woods, living on firs, whereas the others 

 dwell on the banks of rivers and the margins of ponds, upon rushes, 

 reeds, long grass and bushes". L. Koch, loc. cit. , pp. 15, 16. 



T. externa L. Koch and T. obtusa on the one side are therefore 

 easily distinguished from T. Nowickii and T. pinicola on the other 

 by their uniformly coloured sternum. T. pinicola cT is distinguished 

 by having the great spine on the upper side of the mandibles 

 pointed, neither cloven at the apex nor emarginated, as in the other 

 species. It will be probably sometimes difficult to distinguish the 

 female of T. pinicola from T. Nowickii ? by any other token than 

 its considerably smaller size: its cephalothorax is in the specimen I 

 have seen only about half as long as that of moderately sized spe- 

 cimens of T. Nowickii The posterior row of eyes seems to me 

 however evidently more curved backwards in T. pinicola than in 

 T Nowickii. The females of T. externa L. Koch and T. obtusa are 

 sometimes very difficult to distinguish from one another, for also in 

 T. obscura $ the claw of the mandibles has a short tooth at the 

 base, and one cannot always from the colour and from the form of 

 the abdomen determine which of these two "species" one has in hand. 



The spines on the legs of T. externa L. Koch are very variable 

 in length, sometimes long, as in T. obtusa, sometimes almost as 



