22 THE FORAMINIFERA 



seas have rocks been formed, from arctic to tropical climes, 

 even from the Paloeozoic age. To study these is the work of the 

 geologist; but he will tell us that many species which we are 

 familiar with in the British waters of to-day have remained 

 unchanged since the era of the formation of chalk. 



The question of species is one of great uncertainty. Some 

 forms, such as those alluded to, we recognise from Mesozoic 

 times, in which, though now we may find occasional varieties, the 

 type seems constant and all but uniform — as Lagma Williainsoni. 

 Others are so protean that we recognise their very want of stabi- 

 lity, in form. Yet something about the structure makes us 

 unhesitatingly pronounce the aberrant group but one species — as 

 Truncatidina lobatida. Again, we have a genus, whose allied 

 species it is almost hopeless to attempt to dogmatise about, so 

 endlessly do they change and run into each other, where some of 

 the so-called species are definite and clear enough — as the Poly- 

 morphiim. Whilst our knowledge of the life and development of 

 the living animal is so small, we have to put up with a more or 

 less artificial arrangement. 



Patient observation of the living organisms themselves is 

 required to throw a fuller light on the subject, and clear up some 

 points which the systematist requires as data to enable him 

 correctly to interpret some problems connected with the genealogy 

 of these heirlooms of time. 



In taking a general review of the Foraminifera of the gather- 

 ings on this part of the coast, one is struck by a few leading 

 differences as compared with that from many localities in Great 

 Britain. Amongst these may be noticed the absence of Bilocidina 

 i'ingens^ the moderate frequency of Miliolina fiisca and Anwiodis- 

 cus gordialis, and the occurrence of a few fine specimens of 

 Ammodisciis Sho7ieaiia. 



The flattened forms of LagencE are remarkably abundant, 

 giving rise, as might be expected, to varieties, and including some 

 of the rarer forms, among which may be mentioned Lagena pul- 

 chella^ L. faba, L. bicarinata, L. fiinbriata^ and L. dathrata^ the 

 last two not having been before recorded as British species, and a 

 variety between Z. dathrata and L. castrensis. 



Lingtdina carinata is also remarkable. The NodosarincE^ 



