Thorell.] 502 [April 21, 



what darker at the base, with black spots and streaks above, and on 

 the sides ; the tibiae have also distinct blackish lines above, and the 

 metatarsi show traces of three dark rings. The anterior tibia?, seen 

 from the under side, show four pairs of spines, the third pair being 

 inserted on the sides of the joint. Abdomen of a dark olive, or 

 perhaps blackish brown, with traces of a whitish longitudinal middle 

 band in front ; belly paler. The vulva consists of a large, deep, 

 rather transverse fovea, strongly rounded in the sides, truncate, or 

 slightly rounded in front, its edges being behind incrassated into a 

 rounded tubercle on each side ; the margin is in the middle, in front, 

 drawn out somewhat triangularly backwards, and continued into a 

 short narrow septum, which towards its posterior end is rapidly 

 dilated into an oblong lamina, narrowing towards the obtuse apex, 

 and having the form of a narrow, elongated rhomboid, or an arrow- 

 head ; this lamina fills with its hind part the open space between the 

 incrassated and incurved margins of the vulva. By the septum the 

 vulva is divided into two large rounded foveas, showing each in its 

 bottom a paler lamina, rounded in front. Mamillae black. 



Length of body, 9 millim. ; of cephalothorax, 4 millim. ; breadth 

 of cephalothorax, 3 millim.; legs of the first pair, 10.75 millim.; 

 second and third pairs, 10.5 millim.; fourth pair, 16 millim.; patella 

 and tibia of fourth pair, 4.5 millim. ; tibia alone, 3 millim. 



The female here described was captured at Strawberry Harbor, 

 July 28th. It will probably be difficult to distinguish this species 

 from other closely allied forms, e. gr. L. glacialis Thor., and L. aquilo- 

 naris L. Koch, (both from Greenland), by any other characteristics 

 than the rather peculiar form of the vulva. The specimen is very 

 much damaged, and appears to have been left to dry for some time ; 

 this is also the case with the female of the next following species, 

 L. labradorensis. 



10. Lyeosa labradorensis n. cephalothorace nigricanti, vit- 

 tis tribus satis angustis pallidis albicanti-pilosis, lateralibus supra- 

 marginalibus, continuis, in margine superiore paullo inasqualibus, 

 media ad partem cephalicam tantum pertinenti, in medio gemihata, 

 antice sub-truncata, posteriora versus angustata ; palpis pedibusque 

 obscure testaceo-fuscis, femoribus supra et in lateribus nigro-lineatis- 

 maculatisque, patellis et tibiis quoque supra nigricanti-lineatis, ab- 

 domine fusco, vitta media antica abbreviata albicanti; area vulvas 

 elevata, antice angusta, postice dilatata, impressione media in duas 

 partes divisa, parte anteriore sulcis duobus longitudinalibus notata, 

 parte posteriore foveis duabus lunatis obliquis, aream triangulam, 





