Bibliographical Notices. 457 



Tlie different states of this species may be characterized as fol- 

 lows : — 



Striatella tenice/onnis. 

 a. Frustules without transverse striae. 

 /3. striata. Frustules with longitudinal series of transverse striae; the 



two longitudinal striae on each side have a single curve near the 



base. PL IX. lig. 5. /3. 

 y. serpentina. Frustules with longitudinal series of transverse striae, 



the longitudinal striae on each side undulated. PI. IX. fig. 5. y. 



a. Common. /3. Torquay, Mrs. Griffiths, y. Torquay, Mrs. 

 Griffiths ; Hastings, Mr. Jenner. 



In the variety 7. there is also in general a narrow longitudinal 

 space without any markings, and appearing like a white band oc- 

 cupying the centre. 



In the remarks on Striatella unipundata I observed that there 

 were two series of strife. I have since examined this subject more 

 minutely, and find the same structure in TaheUaria, Striatella, 

 Tessella and Tetracyclus. The appearance of longitudinal strise 

 is in fact produced by siliceous plates arising internally from 

 the margins of the filament, and extending towards but not reach- 

 ing the centre. Tlie interior is thus divided into chambers open- 

 ing into a central space. ^Vhen viewed laterally, this central space 

 has the appearanceof a canal, especially as the imier edge of each 

 plate has a concave outline. This appearance is more striking in 

 TaheUaria, Striatella teniaformis and Tetracijclas lacustris, where 

 all the plates are nearly equal ; but in Striatella arcuata, S. uni- 

 punctata and Tessella catena they are shortest near the angles, and 

 gradually longer as they approach the middle. In the latter the 

 outlines of two plates are frequently seen at one time when viewed 

 laterally, in consequence of the unequal size of the plates, Plate 

 IX. fig!! 6. c. 



[To be continued.] 



BIBLIOGRAPHICAL NOTICES. 



The Zoology of the Voyage of H. M.S. Sulphur , under the Command of 

 Capt. Sir Edward Belcher, R.N. SfC, during the years 1836-42. 

 Published nnder the authority &;c. Edited and superintended by 

 Richard Brinsley Hinds, Esq., Surgeon R.N. attached to the 

 Expedition. — Mammalia, by John Edward Gray, Esq., F.R.S. 

 No. I. London, Smith, Elder and Co., 4to. 1S43. 



By the attention of the author or publishers, we have now before us 

 the first part of the "Zoology of^ the Voyage of H.M.S. Sulphur." 

 This is one of the series of zoological works arising from our Voyages 

 of Discoverjs published under the patronage of " the Lords Commis- 

 sioners of the Admiralty :" as such we wish it success, and as public 

 Ann, ^ Mag. N. Hist. Vol. xi. 2 H 



