Hkron-Aij.en and Kaki-anu — Studi/ of Verneuilina pob/strophd. 173 



size of the long and short dwarfs, as compared with tlie uoniial forms, wliich 

 was about as 1 to 10, and their extreme rarity. ]u many of our dredgings 

 the normal V. polystroplia was a common type ; but the dwarfs, even when 

 present at all, formed hut a minute fraction of the specimens, probably less 

 than •! per cent. We had not up to this time identified these dwarfs with 

 the figures of V. pusilla Goes, and in our paper we inclined to the view that 

 they might prove to be the microspheric type of V. polystro/iha, but admitted 

 that there was no evidence to prove this theory. 



Since that time we have devoted a considerable amount of work to this 

 little form V. pusilla, and in view of our demonstration of dimorphism in 

 the normal types of V. polystroplui, our theory of the microspheric nature of 

 V. piisilla must be abandoned. All the evidence we have accumulated tends 

 to show that it is merely an example of dwarfing or nanism. 



V. pusUla is unquestionably very rare. In searching for it we have 

 re-examined some dozens of dredgings in which the normal V. /lolyslropha 

 occurs, but liave added very few records to those previously known. More- 

 over, with one exception, the specimens found in any particular gathering are 

 in the infinitesimal proportion already mentioned. The single exception is 

 a very muddy dredging made in 15 fms. off the Tan Buoy, Millport, in the 

 Clyde area, where V. pusilla occurs in considerable numbers, forming 

 perhaps as much as 1 per cent, of the total specimens of V. piolystropha. 

 From these specimens we have drawn up the following diagnosis of the 

 variety. 



Test free, minute, very finely arenaceous. Colour usually deeply 

 ferruginous, but often white in the later chambers, and sometimes white 

 throughout. Occurring in two forms — (1) a long form gentl)' tapering to 

 the aboral extremity, commencing with a spherical primordial chamber of 

 chitin, without sandy investment, which projects from the apex, followed 

 immediately by a triserial arrangement of sandy chambers regularly 

 increasing in size (figs. 11 and 12). Average length of full-grown specimens, 

 about "3 mm., but attaining at times '4 mm. 



(2) A short form rapidly increasing in breadth owuig to turgidity of 

 chambers. Aboral extreniity, when perfect, terminating in a spherical 

 primordial chamber, but in most of the specimens examined this was wanting, 

 and the test commenced directly with a triserial arrangement of chambers 

 (fig. 13). Average length, -17 mm., but attaining -il mm. 



The long and short forms are exact facsimiles in miniature of the normal 

 V. polysiropha occurring in the same gatherings, but their size varies 

 between one-sixth and one-tenth of tlie normal. The long dwarf form 

 is of much more frequent occurrence than the short, which has uot been 



