140 



SCIENCE- G OSSIP. 



true house-spider, is very local, and by no means 

 common. I have received a number of specimens 

 quite recently from Mr. W. H. Terry, of Brentford. 

 In warmer climates this spider lives in the open air. 



Tegenaria liiberniea Cb. 



Length of male from 8 mm. to 16 mm. 



I am unable at present to give the characters of 

 this species, not having seen either specimens or 

 description. It seems to be confined to Ireland. 



Tegenaria domestica Clk ( T. derhamii in 

 Spiders of Dorset. T. a'vi/is Bl.) 



Length. Male 6. 5 mm., female 11 mm. 



This is the common house-spider, which may be 

 found in disused rooms, cellars, cupboards, and in all 

 such situations. The form of the radial apophysis, 

 the spine on the front of the palpal organs, and the 

 vulva will be quite sufficient to indicate the species 

 with certainty (see fig. XV). 



Tegenaria camp sstris Kcch. 



Length. Male 5.5 mm., female 7.5 mm. 



This spider differs from T. domestica Clk. by its 

 smaller size and by it;- far more distinct markings. 

 The vulva of the female is very typical, and the 

 palpal organs of the male are of an extraordinary 

 form, being highly developed, with several prominent 

 lobes and spines. The digital joint is also very 

 large. This species is usually found out of doors. 



Tegenaria pagana Koch. 



I had the good fortune to take a female of this 

 species near Birmingham in the autumn of 1899. 

 This is its first, and up to the present time its only, 

 recorded occurrence in Britain.. It is a rather small 

 and distinctly marked spider, with the vulva very 

 typical. I am unable to give a detailed description, 

 as the spider is at present in the hands of the 

 Rev. O. P. Cambridge. 



Tegenaria cinerea Panz. 



Length. Male 6 mm., female 8 mm. 



This species is rare. It may be easily distinguished 

 by the pale grey abdomen, which is quite devoid of 

 markings. 



GENUS AGELENA WALCK. 



The spiders in this genus have the legs shorter, in 

 comparison, than Tegenaria. The eyes have a 

 different arrangement, the hinder row being strongly 

 curved, the convexity being directed backwards- 

 They are found amongst low bushes and herbage in 

 ditches, spinning a funnel-like snare of a rather sub- 

 stantial character. 



Agelena labyrinthiea Clk. 



Length. Male 10.5 mm., female 12 mm. 



Cephalo-thorax reddish-brown, hairy, and with 

 two lateral bands of a somewhat darker colour. 

 Abdomen of a dull brown or blackish-brown colour, 

 sometimes tinged with purple. This purplish tint is 

 more noticeable in young specimens. On the upper 

 side of the abdomen is a series of angular bars of a 



paler colour than the general tint. The vulva is 

 distinct and of a rich red-brown colour. The cubital 

 and radial joints of the male palpus have each a 

 prominent apophysis. This is a common, well-known 

 spider, and may be captured as directed for those of 

 the genus Tegenaria. Its web is formed amongst 

 grass and low herbage, and should be looked for 

 during the summer and autumn months. 



Agelena prompta Bl. 



Length. Male 2 mm., female 2.5 mm. 



Cephalo-thorax brown, darkest in front. Abdomen 

 dark brown, with a series of pale angular lines. The 

 radial and cubital joints of the male palpus have each 

 an apophysis ; and the palpal organs have a long, 

 fine spine attached to and almost encircling them. 

 Very rare. 



(7b be continued.') 



ENIGMAS OF PLANT LIFE. 



By Dr. P. Q. Keegax. 

 1. Eaely History of Chlorophyll. 



A CCORDIXG to a note published in 1773. 

 J --*- chlorophyll was first extracted about the 

 year 1750 by alcohol and ether from the tissues by 

 the brothers Guillaume and Hilaire Rouelle. For 

 several years afterwards the green pigment of 

 leaves was considered as analogous to starch, and 

 was called "green fecula." A. Comparetti, in 

 1791, seems to have been the first to signalise the 

 green granules of chlorophyll. In 1807 Link 

 established the distinction between the starch 

 enclosures and the green pigment, and regarded 

 the latter as a colouring resin ; he called it a 

 " resinous colouring matter." In 1817 Pelletier 

 and Caventou named it " chlorophyll " ; they ex- 

 tracted it from the marc of herbs with alcohol, 

 and purified the residue of the evaporated solution 

 by washing- with hot water. They considered it 

 to be very rich in hydrogen, but free from 

 nitrogen. In 1835 Clamor Marquart obtained it 

 by extracting grass leaves with alcohol, evaporating 

 the alcohol, and separating the chlorophyll from 

 the residue by means of ether. In 1837 Berzelius 

 announced the discovery of three very distinct 

 modifications of chlorophyll — viz. those occurring 

 in fresh, dried, and dark leaves ; while about the 

 same time Mohl distinguished between amorphous 

 and granular chlorophyll. He denied its vesicular 

 nature — i.e'. denied that the granules are cells, 

 strictly so called, or rudiments thereof. It was 

 apparently Mulder, however, who first began to 

 suspect that the pigment was not really homo- 

 geneous, for in 1841 he found that by the action 

 of alkalies and acids it could be seemingly resolved 

 into a yellow and a blue substance, also a black 

 matter. Like Berzelius, he likened chlorcgjhyll to 



