CLASSIFICATION AND AFFINITIES 487 



Depth in 

 Fathoms. 



10 to 690. Ehi/ncJioncUa 2>sittacea GmeMu . Shetland and near Dogger Bank. 



This -species is possibly fossil 



as well as recent. 



3 to 808. Crania anomala MiiUer Loch Fyne, North of Scotland 



690 to 2425. Discinisca atlantica King .... W.of Donegal Bay in 1366 faths., 



W. of Ireland in 1240 faths., 



off Dingwall Bay 



Classification. 



The table of classification here appended is that suggested by 

 Mr. Davidson in his Monograph on the liecent Brachiopoda. 



I. TESTICARDINES 



Family. 



A. Terebratulidaic. This includes the majority of genera and of species, the 



latter, without counting uncertain sjDecies, amount- 

 ing to sixty-eight. Examples : Terebratula, Tere- 

 hratella, Terebratulina, ]Valdheimia, Megerlia, 

 Anjiope, Cistella. 



B. Thecidiidae. This family contains one genus, Thecidium, with two 



species. 



C. Rhynchonellidae. This family is made up of eight species, six of which 



l)elong to the genus Rliynclwnella, and two to 

 Atrdia. 



II. ECARDINES 



D. Craxiidae. Tliis family comprises the four species of Crania. 



E. Discixidae. This family contains one species of Discina and six 



of Discinisca. 

 ¥. LiXGULiDAE. This family consists of eight species of Limjida and 



three of Glottidia. 



It is impossible to come to any satisfactory conclusion as to 

 the position of the group Brachiopoda with relation to the rest 

 of the animal kingdom. They have, in accordance with the views 

 of vari(jus investigators, been placed in close connexion with many 

 of the large groups into which the Invertebrates are split up. The 

 ]\Iollusca, the Tunicata, tlie Polyzoa, the Chaetopoda, the Gephyrea, 

 and of recent times such isolated forms as Phoronis and Sagitta, 

 have all in turn had their claims advanced of relationship to this 

 most ancient group. As far as I am in a position to judge, their 

 affinities seem to be perhaps more closely witli the Gephyrea and 

 with Phoronis than witli iiiiv of the other claimants : but I thiidc 



