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the female has no tooth at the base, and in the male’s mandiblesthere is neither a protuberance nor a tooth before the spine on theupper 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 eachother, the male’s mandibles are directed downwards, the spine on theupper side is not cloven at the apex, and in front of it there isneither a protuberance nor a tooth, and the claw on the female’s man-dibles has no tooth at the base. — Tetragnatha obtnsa has a brown-ish yellow sternum with a shade of black, the centre eyes of thetwo 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 ina 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 upperside of the male’s mandibles there is a conspicuous sharp tooth; thefemale’s abdomen is short and thick and is highest arched towardsthe base of its length, and looks almost triangular, when viewedfrom the side. — Tetragnatha pinicola and obtnsa I have constantlyobserved only in dry dark woods, living on firs, whereas the othersdwell 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. obtnsa on the one side are thereforeeasily distinguished from T. Nowickii and T. pinicola on the otherby their uniformly coloured sternum. T. pinicola c? is distinguishedby having the great spine on the upper side of the mandiblespointed, neither cloven at the apex nor emarginated, as in the otherspecies. It will be probably sometimes difficult to distinguish thefemale of T. pinicola from T. Nowickii $ by any other token thanits considerably smaller size: its cephalothorax is in the specimen Ihave seen only about half as long as that of moderately sized spe-cimens of T. Nowickii J. The posterior row of eyes seems to mehowever evidently more curved backwards in T. pinicola than in1\ Nowickii. The females of T. externa L. Koch and T. obtnsa aresometimes very difficult to distinguish from one another, for also inT. obscura ? the claw of the mandibles has a short tooth at thebase, and one cannot always from the colour and from the form ofthe abdomen determine which of these two ’’species” one has in hand.

The spines on the legs of T. extensa L. Koch are very variablein length, sometimes long, as in T. obtnsa, sometimes almost as