Clubiona tibialis.—Quarter of an inch long, the same size and color as crassipalpis, with no markings and no dark color except on the mandibles and male palpi. The middle eyes are a little farther apart than in crassipalpis. The male mandibles [(fig. 54)] are narrower than in crassipalpis and without the sharp ridge on the outer side, but on the inside they are sharply hollowed out with a ridge between the thick outer and thin inner portions. The male palpi [(fig. 53)] have the patella about as long as wide, as it is in crassipalpis and canadensis, but the tibia is very large, with a hook in the usual place on the outer side and a much larger process, which extends forward over the tarsus. The tarsus is long and thickened in the middle where it rests against the process of the tibia.

Clubiona canadensis.—Quarter of an inch long and without markings. The upper eyes are nearly equidistant, as they are in crassipalpis, but the legs and palpi are shorter. The male mandibles [(fig. 56)] are much like those of crassipalpis, but have not so sharp a ridge on the outer side. The male palpi [(fig. 57)] have the patella longer than wide and the tibia wider than long, with two processes on the outer side. The upper tibial process is a simple point extending along the outer side of the tarsus for a quarter of its length. The under process is twice as long, with a projecting corner at its base and running forward to a sharp point, with a round notch halfway between the point and base. The female has the head wider and the mandibles very much swelled in front at the base [(fig. 55)]. The fourth leg is longest and about as long as the body.