September 
THE COTTAGE GARDENER. 
bited at a meeting of the Botanical Society of Edin¬ 
burgh, from the collection at Dalkeith, by Mr. James 
M‘Nab, and created great interest; hut not more than 
was shown by Sir William Jackson Hooker, director 
of the Royal Botanic Gardens at Kew, and Mr. John 
Smith, the talented curator of that establishment, as 
well as by many of the leading botanists round Lon¬ 
don, to whom we also sent specimens. Mr. Bishop’s 
name will long be held in remembrance in every 
garden in Britain, from the circumstance of his origi¬ 
nating two varieties of pea of exceeding dwarf habits, 
and of great precocity and productiveness. The last 
of these, ‘ the Early Long Podded Dwarf,’ is decid¬ 
edly the best pea in cultivation. Mr. Bishop had a 
great taste for music, and was considered one of the 
most chaste violin amateur players in the kingdom. 
His manner was mild and unobtrusive, particularly 
with strangers, yet frank and communicative with 
those he was intimate with. He was doomed to see 
many of the vicissitudes of life, yet, in his most de¬ 
pressed state, had the highest regard to honour and 
integrity.” 
Another pest of the garden has this year forced 
itself prominently into notice by its ravages. We 
allude to the insect which has been and is carrying 
destruction wholesale among our lettuce crops. Upon 
submittiug specimens of the insect to Mr. Westwood, 
the well-known entomologist, lie informs us that other 
specimens have been sent to him, that they belong to 
a species which he did not find anywhere described, 
and to which he has given the name of Pemphigus 
lactucce. The specimens we received were from the 
garden of Mr. Savage, of Winchester. About one 
hundred Green Cos lettuces were planted early in 
July on a light southern border, resting on a clayey 
marl subsoil, it being manured with a compost formed 
of earth, lime, garden refuse, and house sewage, and 
the preceding crop being early peas. During their 
early stages of growth the plants looked vigorous, but 
when they had attained to about half their full size, 
the leaves, after for some time exhibiting a green hue 
unnaturally dark, drooped, as if for want of water, 
and the whole vigour of the plants was departed. 
This appearance did not occur to a few of the plants 
at a time, but the whole of the one hundred were at 
once affected. Upon taking up some of them, the tap 
and fibrous roots were not decayed, but myriads of 
small dirty-white coloured insects were upon them, 
and pervaded the soil in their immediate neighbour¬ 
hood, and then- exuvife gave to it and to the lettuce 
roots the appearance of being mouldy. Mr. Westwood 
informs us that the insect belongs to the winged 
division of the Aphidcc, or Plant Lice, and to Hartig’s 
genus Pemphigus, which differs from the common 
aphis by having its antennas six-jointed, audits wings 
veined more simply, as well as by having no honey- 
secreting tubes at the extremity of the body. 
We thought, with Mr. Westwood, that this species 
had not been previously described, but we have since 
found it was thus very fully noticed, hi 1846, by the 
807 
Rev. Mr. Jenyns, under the name of the “ Lettuce 
Blight:”— 
“ In the summer of 1844 the entire crop of lettuces 
in my garden were destroyed by a blight at the roots, 
arising from the attacks of a small species of Erio- 
soma. This insect had never shewn itself there in 
any previous year to my knowledge. In this in¬ 
stance, all the young lettuces, from six to nine inches 
high, were observed with their lower leaves flaccid, 
and flat on the earth, as if parched from drought: 
tlio older ones, which had been tied up for blanching, 
were some of them completely dead and brown at 
the heart, others dying. No insects were observed 
upon the plants above ground ; but, on pulling them 
up, the fibres of the roots were found thickly matted 
with a glutinous cottony substance, amongst which 
were crawling hundreds of the larvae and pupae. This 
was on the 28th of August, and at that time no per¬ 
fect insects were as yet visible. The larvae were of 
all sizes, some very small, and apparently but just 
hatched: here and there imbedded in the cottony 
substance were the eggs themselves. The former 
were rather active in their movements, of a green 
colour, with six rather short feet, the hinder pair not 
longer than the others; the antennae also short, of 
six joints. The pupae had rudiments of wings, but 
were similar to the larvae in all other respects, except 
in being larger; they were exactly a line in length. 
On placing some of the lettuces under a bell glass, 
several of the perfect insects appeared on the 3rd of 
September; others following in succession for some 
time afterwards. These were of two colours, perhaps 
characteristic of the two sexes. Some had the bead 
and thorax dusky brown ; the abdomen pale dusky, 
tinged with greenish-yellow; the legs dusky, with the 
joints rather darker: others inclined generally to 
ochraceous-yellow, especially the abdomen, and the 
collar between the head and thorax.”* 
“ Amongst the larvae at the roots of one lettuce I 
observed a single specimen of the larva of some other 
totally different insect, which appeared to be feeding 
upon them. This latter was vermiform, and much 
attenuated towards the anterior extremity, which was 
very protractile; it was of a pale green colour, and 
about two lines in length. There were also some 
small brown coccoons among the roots, here and 
there, likewise about two lines in length, which I 
kept in the hope of their turning to the perfect state, 
but without success. Probably these were the larva 
and pupa respectively of some dipterous insect, which 
keeps the root aphis in check. When once, however, 
the nuisance occasioned by this last parasite shews 
itself in a garden, the only effectual way of getting 
entirely rid of it is immediately to pull up all the 
diseased plants and bum them.” 
* “ If the above be an undescribed species of Eriosoma, which is 
extremely probable, from the little attention which has been paid to 
the insects of this family,—it might be named E. lactucce, and thus 
characterized : E. capite et thorace fuscis : abdomine oblongo fus- 
cescenti-ochraceo, vel viridi-ochraceo; pedibus fuscis , articulis satu- 
ratioribus. Long 1. lin.— Hub. ad radices lactucse sativse. Possibly 
it may be the Aphis radicum, briefly alluded to by Kirby and Spence, 
(vol. ii. p. 89,) as deriving its nutriment from the roots of grass and 
other plants. There are, however, without doubt, several species of 
these root Aphides. I have occasionally observed another, besides the 
one described above, at the roots of the Lysimachia numm.ula.ria, 
when growing in a pot in my garden, and rendered unhealthy by being 
kept too dry. This was likewise a species of Eriosoma, but differed 
from the E. lactucce in having the abdomen shorter and broader, (or 
more approaching to round than oblong,) and in being more sluggish 
in habit, hardly attempting to move when taken from the plant; it 
also kept more on the surface of the ground, at the bottom of the 
leaves and stems, than underground, though many might be noticed 
at the roots themselves. Reaumur has given a list of plants, at the 
roots of which he had found Aphides, but the lettuce is not included. 
Hist, dcs Ins. (12mo. ed. Amst. 1738,) tom. iii. 2nd part, p. 80.” 
