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Fuly 24, 1873) 
point out that in its whole structure the flower seems rather 
_ adapted for cross-impregnation by larger insects, and that at 
_ least some varieties are attractive to humble-bees, On this view, 
_ the opening between the two lower anthers, described by Mr. 
_ Kitchener, is necessary for the escape of the pollen, which falls, 
according to Hildebrand, without the help of insects, into the 
_ groove beneath, where it is held by the Jining hairs until removed 
by insects. Besides humble-bees, I have seen the small cabbage 
_ butterfly (Pieris rape) sucking the flowers of a cultivated pansy. 
With regard to V. cornuta, besides the absence of the black 
mark on the style, mentioned by Mr. Kitchener, which is not 
universally present in V. ¢ricolor, it differs from the latter in the 
uniform size of the unvariegated, pale blue, or white flowers, the 
somewhat looser disposition of the petals, the great length of the 
spur, and the sweetness of the flowers at night, all characters 
_ leading to the belief that it is, in fact, a pansy (if I may use the 
word in a sub-generic sense), adapted to uniform conditions of life, 
_and to fertilisation by /Voctuide. A comparison of the present 
condition of two beds of this species in our garden, in connection 
_ with their surroundings, helps to strengthen this belief, of the 
practical truth of which I have been able to satisfy myself by 
the capture of Cuct/lia umbratica in the act of sucking the 
flowers. One of these beds, in an exposed part of the garden 
_ little frequented by moths (as I can testify from long experience), 
- still displays a profusion of blossoms in all their virgin beauty, 
with only a few small capsules among them ; in the other, ina 
sheltered nook, an old favourite ‘‘ mothing-ground,” the flowers 
are mostly past their prime, and a great number of well-filled 
capsules arejalready formed. By day I have seen the flowers 
visited by a few humble-bees, which seemed to have difficulty 
in reaching the nectar, and by the meadow-butterfly (ipparchia 
Fanira). Hosts of small flies run over the petals in bright sun- 
shine, but rarely attempt to enter the nectary, and I have never 
seen such an attempt succeed. A remarkably long-beaked fly 
which I watched feeding on the pollen, as it repeatedly inserted 
and withdrew its proboscis, must probably have left some of the 
flower's own pollen on the stigma. W. E. Hart 
Kilderry, Co. Donegal, June 22 
Spots on the Cherry-laurel 
CAN any of your readers tell me of what use to the plants are 
the small spots—glands I suppose—on the back of the laurel- 
leaf near the bottom of the rib? Sometimes there are two pairs,” 
sometimes one ; but no leaves seem to be without them. They 
are most apparent in the young leaves. They evidently contain 
something delectable to the bees, which frequent the laurels very 
much this year, and always fly to these spots upon the leaves ; 
and the microscope shows a drop of liquid. ‘J. M. H. 
Sidmouth 
Your correspondent means, “I suppose, the cherry-laurel. 
His observation is quite correct ; such glands are to be found in 
similar situations on other leaves. I know of no explanation of 
their purpose or origin. W. T. THISELTON DYER 
Turnham Green, July ro 
Halomitra 
THERE is a singular morphological coincidence between the 
specimen of Orditoliles tenuissimus Carpenter, figured on p. 91 
of ‘*The Depths of the Sea,” and several specimens which I 
have seen of the corallum of a species of the Aungia group, 
genus Halomitra Dana. The Orézfolites has the appearance of 
having been developed on a nucleus formed by a frustum of a 
former specimen. ‘The outer rings are altogether unconformable 
with those of the truncated segment composing the nucleus ; and 
it is somewhat interesting to notice, as illustrated by the figure 
in Prof. Wyville Thomson’s work, how the growth of the 
Foraminifer, oppressed at the corners and advancing Jer saltum 
at the excavated sides, has shaped itself towards the completion 
of its normal disc-like form. 
An appearance precisely similar has come under my notice in 
the corallum of Ha/omitra. Two specimens in the Free Public 
Museum, Liverpool, from the Solomon Islands, exhibit this 
peculiarity, and of about eight or ten other specimens seen by 
myself, I cannot recollect more than one in which the large 
frustum of a former corallum, constituting an unconformable 
~ nucleus, did not distinctly appear. 
In a single case the presumption would be altogether in favour 
NATURE 
245 
of attributing the peculiarity to an accidental fracture of a former 
corallum ; but its frequent occurrence suggests that it may be 
worth while to inquire into the possibility of spontaneous fission 
taking place in the adult Ha/omitra. Some of the Fungide are 
said to possess powers of limited locomotion. It is quite con- 
ceivable that a great extension of size in the coral might interfere 
with its mobility and render division advantageous. That the 
Zoantharian Actinozoa are able to re-absorb solid portions of 
their coralla is variously illustrated, no example being more 
familiar than that of the young of several species of Fumngia, 
which are attached to the under side of the parent polype by a 
strong neck of ccenenchyme, which is subsequently absorbed 
and the young are liberated. 
Rainhill 
Henry H. Hiccins 
Periodicity of Rainfall 
I HAVE observed in recent numbers of NATURE a discussion 
upon the subject of the Periodicity of Rainfall, and its connection 
with sun-spots, and I hoped by an examination of the Rainfall 
Returns of this island (Barbados), which I have collected for 
30 years, 1843 to 1872, to have been able to confirm the theory 
broached by Mr. Meldrum and Mr, N. Lockyer, which is so 
interesting in itself, and might lead to such important results. 
But assuming that sun-spots affect all parts of the globe equally, 
and that periodicity prevails in all alike, the experience of Bar- 
bados is opposed to the theory, and I am led to the conclusion 
that it was ‘‘ chance alone” that led to the coincidences noticed 
by Mr. Symons in his letter published in vol. viii. p. 143. 
In the following calculation I state the years separately in 
order to show that not only the triennial and quinquennial 
averages, but the individual years, contradict the theory. I am 
able to furnish six periods—three of maximum and three of 
minimum sun-spots. Of the triennial averages two of each show 
an absolute equality ; in the third the rainfail is in an oposite 
proportion to the sun-spots. The quinquennial averages do not 
materially disturb those results. As regards individual years, 
the rainfall was much above the average in two of the minimum 
sun-spot years ; and was above it only in one of the maximum 
sun-spot years; in the second it was an average ; in the third 
it was excessively below it. The average of the island for 25 
years, from 1847 to 1871, is 57°74 inches, based upon the mean 
of 3 stations in 1843, and increasing to 141 in 1871. 
Yearly Average of Average of 
Rainfall. 3 years, 5 years. 
43 45°31 
Minimum 1844 74°45 54°56 
45 43°91 
46 65°82 
47 48°10 
Maximum 1848 63°77 54°86 59°67 
49 52°77 
50 67°88 
54 50°38 
ee 55 77°31 
Minimum 1856 48°49 62:23 56°56 
57 60°90 
58 45°22 
58 45°22 
59 56'22 
Maximum 1860 57°91 61°98 58'09 
61 73°82 
62 59°27 
65 68°64. 
66 59°68 
Minimum 1867 69°93 58°07 58°27 
68 44°60 
69 48°52 
69 48°52 
7° 60°17 
Maximum = =1871 41°46 50°00 52°71 
72 48°39 
73 65°00 
T hie ventured to estimate the rainfall of the present year 
with much confidence upon the data given in the accompanying 
notics, with which I need not trouble your readers. 
_ Barbados Rawson W, RAwson 
