2. Some Falklan dc Island Spiders. By II. It. HOG G, M.A., F.Z.S. [Received October 8, 1912 : Read November 12, (Phttes I. (Sr, II.

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1 ,c. e hg- `, Some Falklan dc Island Spiders. By II. It. HOG G, M.A., F.Z.S. [Received October 8, 1912 : Read November 12, (Phttes I. (Sr, II.* ) INDEX. Pag e Systematic : Araneus vallentiui, sp p. n. 37 Araneus globiger, sp. 1i Tetragnatha insulata, sp. n 4 1 Philisca colulata, sp. n 42 Enanenonma fallclandica, sp.» Petricus signatus, sp. D 4 6 Sadocus vallentini, sp. n The small collection of spiders from the Falkland Island s cue 4cribed below was brought to this country by Mr. Rupert Vallentin, who has been good enough to afl0rd me the opportunity of examining them. Connected generically with Patagonia and the Magellanic Region, they are all apparently new species. Gathered as they have been over a, period of two years, they comprise only si x species of spiders and one Opilio, of sorense n 's genus,s'w/ocus, with a fair number of specimens of some of the species. Three of these are Argiopidm which are easily conveyed by th e wind, and supply no argument for a former land connectio n between these islands and the mainland of America.. Family A.RGI0PID1E. Group.AI56IorEE. Genus A.ISANEIJS Clerck. ARAN +'ITS VALLEN'I'INI, sp. n. (Pl. T. figs. 3-3 e. ) The colour as seen in specimens taken from spirit is a s follows :--- Cephalothorax pale yellow-brown with longitudinal streaks o f long white hair, rather bare on the sides but a pale margina l streak all round. Mandibles pale yellow-brown at the base, dar k brown at the apex. The fangs are dark brown a,t the base, dingy yellow-brown at the points. For explanation of the Plates see p. 56.

2 48 i\'ift. Ii. R. HO((a O N than those on the other joints. They are not divided longitudinally as in 111iseoneua. The inner of the pair of tarsal claw s has about three rather long pectinntions on the shaft curving with the curved point of the claw. The palpi are short and fine, with hair and bristles as on tir e legs, and spines on the tibial joint. The measurements (ill millimetres) of the largest are a s follows : - - Lour. Broad. ('t pha,lothorax... 32i 1_} in front. Abdomen Mandible Legs Palpi 5 1 :} Pat. & :li(t ; t. ('ox ;r, Tr, fenr, tit,. (L tars ' 1 r l ~I -~ :L ,. 1 1 I. = 4 This species conforms to M. Simon 's genus Petricas from South America, and is closer to his I'. niveus than to any of Mr. Tullgren 's species. It differs, however, from the former i n its front row of eves being very clearly r.e(,urv(d instead of slightly ; the median are 3 diameters apart instead of one, and nearer to the lateral than to one another instead of e(ira_i(listarrt ; th e lateral eyes of the front and rear rows about 4 diameters apar t instead of l ; the area of the median (lul,drilateral equally broa d in front and rear, instead of much broader in front. The fron t pair of legs are longer and the others shorter in proportion to tir e cephalothorax than in P. 'nilve~rs. There are nitre females from various districts, apparently th e same but differing irr sire of adults and brightness of colour. OPILIONES. Family (w 0 N V L E P 1' 0 1 1) E. (.g enus SA-nocus Sou. SAUOCUS VALLENTINI, sp, Ir. (Pl. 1i. figs. 7--7c. ) Carapace yellow-brown mottled with black-brown anteriorly, nearly all dark brown at posterior en(1 ; eye-tubercle yellow i n middle, black-brown it each side. Trochanters yellow ; other joints yellow mottled with black - brown ; anterior ends of tarsi of rear two pairs yellow with yello w

3 FALKLAND ISLAND SPIDERS. 4 t claws. Hair generally pale yellow-grey. '.1'1-1e under side of th e abdomen is paler than the upper side, having more y(llow and les s dark mottling. The eye-tubercle is oval, twice as broad as long, the eyes bein g at the extreme si(le edges. :It is situated in the front half of th e cephalic part, the portion in front of it being its own -width an d twice that (1iStance [whim]. Tile thoracic part off' f~lie carct))lce is slightly convex with a distinct rnra,rgiintl sulcus a,ll round. There are s quall globular tubercles in the median area of the cephalic part, but not extending to the sides, reaching from the eye-tubercle to Idle rear margin. There are smaller sparsely scattered granulations on the second, third, and fourth divisions of the scutum, aand a trail of tubercle s on the latter. Behind this are four seglraental divisions thickl y covered with tubercles, succeeded by a posterior broader margina l area, also t ibei. ifel oias, which ends, in the, female, in a media n pointed process as long as the roar troclia,nter s. In what appeal's to be the male this is wanting. On the under side of the carapac e the flat coral areas of the second an(l third pairs of legs extend to a narrow sternal depression, those of the.first pair to roun d the' mouth-parts. 'There is a small lower lip above the sternu m and movable chitinous nraxillle unconnected with the coxa of th e pales. A much larger upper lip is divided into two parts o n the under side by a muscular double wall. On the under side of th e tibial joint of the palp are three spinous processes on tho outer margin, and. four on the inner-'. On the tarsal joint of same are four spites alternately:long and shorn on the outer side, and thre e on the inner side of the faa,lx-slaeatll. The long, slightly curved, movable fang is about the length of the tarsal joint. 'tin mandibles reach alp to about the anterior end of the i atell :.u- joint o f the palp. There are three equal teeth on. the insnle of the.fixe d Claw, one large between two smaller on the Movable claw. The coxal area of each of the foru'tli pair of legs is twice as broad a s the median portion of the thorax lying between then.. They extend along each side twice the length of the three anterior coxa l areas. At the posterior end of this coxa ra, chitinous process project s from the outer corner as long as the breadth of the trochanter in the females, and twice that length iil the males. Behind thi s is a round convex boss. At the posterior end of the median area, lying between th e fourth coxae, are the pulmonary apertures with oval convex lids, a ml on the in nor side betii' een tiles(' are a pair of oval w depressions. The three anterior pairs of legs aa_ e of about the same diameter, rather slender, all without spines but covered with short hair. On the tarsal joint of the third and fourth pairs are two curve d smooth claws. ~Tarsus 1 has five joints ; tarsus 2 eight ; tarsu s 3 and 4 six each. The trochantal joint of the fourth pair is a s long as broad and thickly covered with spinous tubercles,.pazoc. ZOOL, Soc. 1913, No. IV. 4

4 50 ON FALKLAND ISLAND SPIDERS. The femoral joint is thickly covered with long chitinou s spinouts processes, which in the male are twice as long as in th e female. The patellar joint is enlarged and globular, the othe r joints are without spines but thickly covered with hair. The measurements (in millimetres) are as follows :--- Long. Broad. (_;ellliali e part of scutum (1 Sternal "Abdominal do. (lo Mandibles 2 Le!;s I. 2. Pi(,lta C' oxal part. '1' r. & tern. 3 4,., Pat. & i f tat. tib. & tars ~a 1 This differs from ~S. r tellinosu icatus Sor. (believed to hav e come front S. America and described from a single female) in. having a single terininal process above the anal tubercle at th e posterior end. of the abdomen, instead of a pair of quite smal l ones ; In having the anterior edge of the scutuni straight instead. <7 a of two pointed processes in the nri(lcllc. ; in having no spine o n the femoral joint of the palpi and Ito pattern on the back of th e abdomen, as well <1s iii its smaller size. '_'here is no process on th e eye-tn"lo., 1e. (_)ile male, b females and 2 non-adult, found,among decayin g -roots of ferns. EXPLANATION OF 'I"IIE PLATES. PLATE I. Fig. I'c/ric1r,s sigru(tv s, sly. Ir., X 3. a. P.:yes. b. Lip a,nd maxi lw. e. Epigyne. 2. Ihflm e (rnm)ua fal/'laizdica, sp. rr., X 2. a. Eyes. b. Epigyne r aaeus '(Sallennt(f'i,, sp. n., nat. sire. a. Underside of abdomen. h. Profile. e. Front of cephalothorax and eyes. d. Lip and niaxilbe. e. Epigyne. 4. Aromas globiger, sp. n, nat. si3' i.e.,. a. Eyes. To Male palp from side. c. Male palp from underneath. (l. Tibia I I. e. ('oxa I. l'late H. Fig. 5. Philisea (OGU.(lata, sp. n., X 2. a. Eyes. b. Mandible. c. Epigyne. d. Spinnerets. 6. a..eyes of Tctraglatba 0(sulata, sp. n. h. (underside of mandible, 4. e. Fore-end of mandible from above. d. Male palp. e. Epigyne. 7. Sa(Ioeus vallerztlfli, sp. n., X 2. a. Underside of carapace. b. Mouth parts. e. Mandible and 1(11lt p,

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