Jan., 1890. 
HELIX (MACULARIA) PUNCTATA. 
19 
rearrangement of the molecules, and also with the obser¬ 
vations and experiments of Fouque cited above, on the 
artificial formation of minerals. 
In the glassy rocks we frequently find approximately 
spherical or spheroidal masses of stony aspect which are 
called splierulites. These are of various kinds ; some consist 
of the globulites previously mentioned, simply aggregated 
into masses something like little blackberries—these are called 
cumulites. In the most typical, however, the elements of the 
splierulite are distinctly crystalline and arranged radially, so 
that in polarized light they show a dark cross. If the 
crystalline elements are either less strictly radial in position, 
or consist of some mineral in which the directions of 
extinction are not in every section parallel to the length of 
the crystal, or finally if they are of different minerals, the optical 
behaviour of which is different between themselves, the black 
cross is not seen. Splierulites often seem to be the latest 
production in the glassy rocks, for they are frequently 
attached to and enclose more or less completely the larger 
crystals, and where there are streams of microlites we can 
usually trace these right through the splierulite, proving that 
this has been produced after the stream of minute crystals. 
Occasionally spherulites coalesce to bands, or even spread 
through the whole substance of the rock. A capital instance 
of the latter is seen in the spherulitic felsite of corriegills, 
shore in Arran. 
NOTE ON THE MORPHOLOGY OF THE GONADS IN 
HELIX ( MACULARIA ) PUNCTATA , MULLER.* 
BY JOSEPH W. WILLIAMS. 
Mr. W. D. George, of Charlton, London, S.E., having 
sent me a living specimen of a Helix which he collected 
at Buenos Ayres, in October, 1888, and which I find is 
referable to the Helix ( Macularia ) punctata of Muller, I 
dissected out the gonads—the subject of the present com¬ 
munication. I need not here sketch the morphology of the 
generative apparatus of a typical Anisopleural Gastropod, 
since I have already done this in my “ Land and Fresh-water 
Shells,” and it will also be found in the majority of our 
* Mr. George informs me in an accompanying letter that this 
species is largely eaten by the Italians in Buenos Ayres, and he 
testifies from practical experience “ that when cooked with oil and 
garlic they are exceedingly palatable.” 
