250 



HARD WICKE' S SCIENCE- G OSSIF. 



joints, having the anterior inferior corner projecting 

 somewhat like a claw ; whilst to the anterior superior 

 angle is articulated the fifth joint — this latter, claw- 

 shaped and very movable — forming with the anterior 

 inferior angle of the fourth joint a very powerful 

 pair of pincers, reminding one of the large claw of a 

 crab, or perhaps rather more like the beak of a parrot ; 

 and this resemblance is very striking when one of 

 the creatures is confined alone, with a little water, 

 under a piece of thin glass, for it then continually 

 moves the palpi, and at the same time snaps the 

 pincers, as if angry. This family is a very numerous 

 one : Koch describes and figures forty species, some 

 of which however have palpi distinctly different from 

 those I have figured and described (they ought 

 therefore to be removed, and will not be considered 

 by me as Arrenuri). They vary extremely in their 

 general appearance, some of them being grotesque 

 in shape, and most of them very beautiful in colour, 

 not only when alive, but also when mounted. They 

 are sometimes called hump-backed mites, and the 

 males of many of them have received the name of 

 tailed mites — a very appropriate title, as will be pre- 

 sently seen. I shall divide them into two sections, 

 from the nature of their skin :— 



1. The Chitinous, or hard-skinned. 



2. The Membranous, or soft-skinned. 



The first division is the more numerous, and con- 

 tains the tailed mites"; from the hardness of their 

 integument they can be mounted in balsam, without 

 losing their shape. This integument looks as if com- 

 posed of separate perforated plates joined together 

 (fig. 177), reminding one of a coat of mail ; it has also 

 on it a most remarkable and deeply impressed 

 more or less oval or circular line, complete in the 

 female, but open behind in the male ; the chitinous 

 skin is so much thinner along this .impressed line 

 that it is not difficult to detach the central part from 

 the rest of the body of the mite, tearing at the line, 

 just as a piece of paper tears most readily where it 

 has been folded. 



Fig. 178 shows well the granular and perforated 

 chitin skin, and also the impressed line ; there are a 

 few long bristles, more conspicuous at the hinder 

 part. Koch lays great stress on these bristles, saying 

 there are four or six of them, and he uses their pre- 

 sence or absence as a character to distinguish one 

 family from another. With regard to the colour of 

 these mites, it is somewhat variable, and much 

 depends upon the contents of the bodies, but some is 

 inherent in the chitin skin, and is usually blue, green, 

 or yellow : the blue becomes a very beautiful one 

 when the mite is mounted in balsam. With regard 

 to shape, the males differ so greatly that each one 

 needs a figure ; also there are several types of form in 

 the females, but I have not found it easy to pair the 

 males and females, only in the case of Arrcntiriis glo- 

 hator, am I satisfied on this point. The legs are 

 rather short, the front legs being the shortest, and 



the hind ones the longest ; ' the swimming bristles,, 

 attached to the three last joints but one, are few on 

 the first pair, and most abundant on the last. The 

 thigh plates are minutely granular. The eyes are 

 large, far apart, and with some lights appear to be of 

 a very beautiful carmine colour in most species. 

 When confined in a glass vessel of water, the females 

 will lay their eggs on the glass : they are generally of 

 a pinkish colour, and surrounded with a whitish 

 opaque substance, which seems to be the material 

 used to fasten them to the glass. When the eggs 

 hatch, a minute larva is produced, which has but six 

 legs ; from their appearance I have no doubt that they 

 then become parasitic, but I have not yet discovered 

 what creature becomes their host — this, indeed, on 

 account of their minute size, will be somewhat difficult 

 to make out. Here then is a problem for observers, 

 which must be solved before the complete life circle 

 of the Arrenuri can be said to be thoroughly known. 



NOTES ON THE NATURAL HISTORY OF 

 SPAIN. 



SPAIN is a country which has not yet become 

 very familiar to English tourists. Moreover 

 those of our countrymen who do visit it, are oftener 

 students of art than of nature. Hence a few 

 observations made during a month's stay in the 

 peninsula, chiefly in Andalusia, may be worth 

 recording. The traveller who has left Madrid by the 

 evening express awakes to a new world when the 

 breaking dawn reveals to his sight the picturesque 

 neighbourhood of Cordova. Long lines of glaucous 

 aloes form the hedges, with their graceful leaves and 

 gigantic flower-stalks. Another favourite hedge- 

 plant is the prickly pear {Cactus of initio). Its 

 outline appears very novel and grotesque to an 

 Englishman, but its bright yellow flowers, which 

 were just expanding at the beginning of May, are 

 very attractive. It certainly forms a most effective 

 fence, for the wounds inflicted by its spines are 

 extremely painful, as I can testify from experience. 

 Some fine specimens of the date palm exist both at 

 Seville and Cordova. Those planted in the court of 

 oranges at the latter place are of great age and very 

 beautiful. 



Of wayside flowers, a large pink convolvulus is 

 abundant throughout Andalusia, flourishing in the 

 driest situations. A tall Echium was also very 

 conspicuous. On the spurs of the Sierra Morena, a 

 charming dwarf Iris, not more than four inches high, 

 made gay mauve patches, and in waste places there 

 was a fine display of crimson Gladiolus. Upon the 

 trees there climbed a graceful creeper with deep 

 purple tube-like flowers. The natives called it the 

 candle plant- 

 In the neighbourhood of Granada the damp woods 

 were profusely decorated with the mauve stars of 



