428 Miscellaneous, 



fishes discovered by Mr. Salwey in the Old Red Sandstone of Actonr 

 Beauchamp, and others by Mr. Lightbody in the upper bone-beds 

 near Ludlow. From the first-named locality the author described 

 a portion of a cephalic carapace, indicating a large and new species 

 of Cephalaspis (C. Salweyi). Another new species of Cephalaspis 

 (C. Murchisoni) was founded on two specimens obtained by Mr. 

 Lightbody in a bed below the paper-mill on the river Teme at Lud- 

 low ; and a third new species (C. ornatus) was described from spe- 

 cimens from dark micaceous shales in the Hereford Railway Cutting 

 at Ludlow. The same shales have afforded two specimens of a very 

 small Cephalas])id of great interest. These are of the size of a four- 

 penny piece, and have a general resemblance to Cephalaspis, except 

 in the peculiarity of having behind the cephalic shield, and united to 

 its posterior margin by a distinctly marked suture, a broad plate 

 divided into lateral halves by a prolongation of the occipital crest. 

 The author, having stated his reasons for regarding these specimens 

 as adult and not embryonic individuals, gave this new Cephalaspid 

 form the generic title Auchenaspis (on account of its nuchal plate), 

 and described it under the specific name of ^. Salteri. In conclusion, 

 some other ichthyic remains, referable to Plectrodus and Onchus, 

 were enumerated as having been collected by Mr, Lightbody in the 

 railway- cutting and in the River-bed near Ludlow. 



MISCELLANEOUS. 



Observations on the Generation of the Arachnida. 

 By E. Blanchard. 



Since Bonnet's experiments on the Aphides, naturalists have fre- 

 quently paid attention to the faculty attributed to the females of cer- 

 tain articulated animals, of engendering without the aid of any male. 

 Thus it has been asserted that some female spiders, kept in captivity 

 and isolated, frequently deposited fertile eggs, and that these broods 

 might succeed one another for several years. From this observation 

 it appeared natural to conclude that in this case the males were aot 

 always of indispensable utility in the continuation of the species. In 

 connexion with this, one of the results of my investigations into the 

 anatomy and physiology of these animals appears to me to be worth 

 recording. 



It is very true that female spiders, when isolated in boxes, furnish 

 eggs which are soon hatched, and this after a captivity of three or 

 four years, Speciniens of Mygale sent from Montpejlier to Paris, 

 and each contained in a separate box, have repeatedly furnished me 

 with a great number of young ones. A Segestria (S. joer/^t/a, Walck.) 

 which I have kept alive for more than three years, produced young 

 the year before last, and again last year j hardly a month ago hundreds 

 of the young were still living. Another form of the order Araneida, a 

 Filistata bicolor, which has also lived for three years in my laboratory, 

 constructed its nest some months ago, and soon afterwards gave birth 

 to a considerable quantity of young individuals which are still alive. 



Such facts as these certainly appear at first sight to allow us to 



