284 



The most abundant Norlosarias are those identified as N. abyso- 

 rum and N. rugosa, both to a certain degree anomalous, the first 

 an account of the pol3'mucronate apex, the latter on account of 

 the peculiar structure of its test. In the columns of the appended 

 table relating Lo the Trinidad rocks an attempt has been made to give 

 an idea of the relative frequency of occurrence of each of the forms 

 naoied. Txii> h i^ baen done according to the following scale : — 



M. represents 1000 examples or more. 



„ 500 to 1000 examples. 



100 to 500 



.u „ 50 to 100 



10 to 50 



V. „ 5 to 10 



1. „ 1 to 5 



For Ihe other localities I could not add such indications, 

 being with;)ut, any information as to relative frequency of occur- 

 rence. I fee! sure that many if not all the gaps in the table will 

 hereafter be fii;ed up when sufficient search has been made for 

 rocks of cone iponding age and conditions of deposit. We have 

 information of the occurrence in Cuba and Haiti of oceanic beds. 

 The LaVile c,e.ii-Iy shows the strong resemblance between the fossil 

 for.uninifeiMl faunas of Trinidad and Barbados. 



The tab.e is not intended to give an exhaustive list.* There 

 are many ohei- forms in my collection. Even of the forms ranked 

 under the names here given some have marked and constant 

 dili'erences which might intitle them to varietal distinction. 



*I miijht alrio add that if my object had been to give a long list of 

 names J mi^ht have almost doubled the number given in the table, so 

 numerous are Uie varieties occurring in the Trinidadian rocks. 



