REPORT ON THE FORAM1NIFERA. 
50 
one point or other ; and the aim of the systematist is well attained if the anomalies and 
inconsistencies are slight, and are confined to matters of small zoological importance. 
The subjoined synopsis needs but little explanation. It is not entirely new, for a 
brief outline indicating its general features was given in one of the preliminary notices 
of some of the Challenger Foraminifera 1 ; but its scope has been enlarged, and many 
amendments have been introduced in matters of detail. 
The nature of the investment of the animal, that is to say the minute structure of 
the test, has been abandoned as an exclusive basis for the primary division of the Order. 
Under all circumstances it furnishes important characters, and in some Families is really 
distinctive ; but it is nevertheless a fact that whilst there are certain groups which are 
invariably arenaceous, and some which are always calcareous and perforate, there are yet 
others in which no uniform rule obtains. In the absence of any simple and easily 
recognised characters to serve the same end, the entire Order has been divided directly 
into Families, without the interposition of Sub-orders. 
The Gromidce, a Family composed chiefly of fresh-water organisms, have been a source 
of considerable trouble, on account of the want of accuracy and detail in the published 
descriptions of a number of types, more or less closely allied to the group; and only such 
genera have been included as are known to have long reticulated pseudopodia. In this 
portion of the subject I have had the advantage of the advice of my friend Mr. W. 
Archer, F.R.S., of Dublin. 
The Sub-family Dactyloporince , which in the original draft was placed, with some 
reservation, amongst the Miliolidce, pending the fuller publication of the results of M. 
Munier-Chalmas’ researches, is now entirely omitted. The examination of specimens 
brought under my notice by Dr. E. Perceval Wright of Dublin and M. Schlumberger 
of Paris has removed any doubt left on my mind as to the propriety of the transfer 
of the entire group to the Calcareous Algse ( Siphonees verticillees and Siphonees 
dichotomes). 
The singular genus Bathysiphon of M. Sars, which was also placed provisionally 
amongst the Miliolidce, has been removed to the Astrorhizidce, inasmuch as further 
investigation of the structure of the test has revealed its close affinity to Carpenter’s 
genus Pilulina. The position and treatment of Parkeria and its allies have likewise 
been somewhat modified, and many other minor alterations have been made, which it is 
hardly needful to enumerate. 
The table has been devised so as to be of service as far as possible in the identification of 
specimens, and the salient characters of genera are very briefly stated ; but from what has 
been already said, it will be easily understood that in certain cases the terms employed 
are descriptive rather than in any strict sense distinctive. No verbal description, nothing 
indeed but experience and the familiarity derived from a patient study of the variations 
1 Quart. Journ. Micr. Sci., 1881, vol. xxi., new series, p. 43. 
