SB

COS
R5W6

Ent.

m.,i

iJM

SOME ACCOUNT

'PALAN BYOO'or 'TEINDOUNG BO'

( Parapoiiyx oryzalis),

A LEPIDOPTEROUS 5NSECT-PEST OF THE RICE-PLANT IN BURMA
WHICH IN THE CATERPILLAR STAGE BREATHES WATER BY MEANS
OF TRACHEAL-GILLS.

BY

J. WOOD-MASON, Esq.,

OFFICIATING SUPERINTENDENT, INDIAN MUSEUM, AND PROFESSOR OF COMPARATIVE
ANATOMY AND ZOOLOGY, MEDICAL COLLEGE, CALCUTTA.

CALCUTTA:
PRINTED BY THE SUPERINTENDENT, GOVERNMENT PRINTING, INDIA.

1885.

'if\\W

Sloctton. Collf.

^$OME ACCOUNT

'PALAN BYOO'or 'TEINDOUNG BO'

( Pavaponyx oryzalis),

A LEPIDOPTEROUS INSECT-PEST OF THE RICE-PLANT IN BURMA
WHICH IN THE CATERPILLAR STAGE BREATHES WATER BY MEANS
OF TRACHEAL-GILLS.

J. WOOD-MASON, Eso.,

OFFICIATING SUPERINTENDENT, INDIAN MUSEUM, AND PROFESSOR OF COMPARATIVE
ANATOMY AND ZOOLOGY. MEDICAL COLLEGE, CALCUTTA.

CALCUTTA :
PRINTED BY THE SUPERINTENDENT, GOVERNMENT PRINTING, INDIA.

1885.

m

SOME ACCOUNT

OF THE

'PALAN'BYOO' OR 'TEINDOUNG BO'

( Paraponyx oryzalis),

A LEPIDOPTEROUS INSECT-PEST OF THE RICE-PLANT IN BURMA
WHICH IN THE CATERPILLAR STAGE BREATHES WATER BY MEANS
OF TRACHEAL-GILLS.

TN January 1882, two specimens (two stages) of a
blight which attacks the Rice-plant, the one called in
Burmese ' Teindoung Bo,' the other ' Palan Byoo,' were
forwarded* for determination to the Indian Museum by
the Chief Commissioner of British Burma together with
the subjoined translation from the Burmese of a Memo-
randum! on different kinds of blight by Assistant Set-
tlement Officer Moung Too.

These specimens are in reality three in number — one
being a caterpillar and the other two pupae or chrysalises,
and they represent two of the stages in the metamorphosis

* In British Burma Revenue Settlement Department No. 1417, General,
January 9th, 1882.

f The different blights to which paddy is liable are said to be four ;
they are —

(1) Ywetpyatpo ; I (3) Satmee;

(2) Pinbo (or Ooshoukpo) ; | (4.) Palanbyoo.

Ywetpyatpo. — When the paddy is about a foot above the ground this
blight first appears ; it is not of a very serious kind. The paddy does not
usually die ; it loses its leaves and is weakened. This insect first appears as
an egg on the paddy ; after three or four days it becomes an insect, enters into
the folds of the leaf, nibs it, and lets it fall off. The appearance of this insect is
much like a cricket ; its colour is green-spotted. When this blight appears
it is desirable that there should not be an excess of water in the fields ; the

2 RICE-PEST OF BRITISH BURMA.

of a small animal belonging to the Heterocerous divi-
sion of the insectean order Lepidoptera.

They differ, as will be seen, so little from the corre-
sponding stages of an animal whose metamorphoses are
completely known even to the minutest detail, that they
may, even in the absence of the perfect insect, be
accepted with entire confidence as stages of a closely-
allied species of moth.

The ' Palan Byoo ' is an animal of considerable zoo-
logical interest, inasmuch as in its larval stages it is
specially modified for a purely aquatic life ; having the

water is therefore drawn off, for, should the leaves of the paddy be parti-
cularly green and tender, the destruction of the leaves would be excessive.
This description of blight is liable to occur from Wagoung (July) till
Tawthalinlabyee (September).

Pinbo. — Pinbo, otherwise called Ooshoukpo. This is probably only the
above-described insect under a different name; also called Teingdoungbo.

For of the insects who nipped the leaves some remain, some are carried off
with the leaves, and eventually, wafted by the wind, attach themselves to
plants, and crawl up the hollow of the stalk. This blight is liable to occur
from Tawthalin (September) to Thadingyoot (October). Should it then
appear, the leaves turn white and shortly afterwards some plants die off;
the remainder are weakly and do not fruit well.

Satmee. — The above description of blight is frequently also described as
' Satmeelikethee.'

This blight is called after a "sambur's tail." The root of the plant
bushes out, and the extremity, instead of sending out fruiting shoots, remains
as it is. When this occurs some plants die off outright ; some that remain
do not increase from the main stem, but branch off the top, and when the
time for fruiting comes do not fruit well. This description of blight
generally occurs in very good (rich) soil. Should it appear, water should
be let "into the field, for, should there be a deficiency of water, the paddy is
sure to die off. This is also called ' Bouktheik,' and occurs in land flooded
by salt-water.

Palanbyoo. — Palanbyoo is another' description of blight. It is a flying
insect which settles on the paddy. Paddy so attacked discolours. The
insect itself is something like the rice-insect. Because paddy so attacked
gets white (discolours), this insect is called Palanbyoo. It is not a very
destructive kind of blight, and generally occurs from Tawthalin (Septem-
ber) to Thadingyoot (October). When it appears, the water is let out of the
fields and consequently the plants dry up, and, when fruiting, do not fruit
well. After 10 or 15 days the insect leaves the plants and flies away. By
some cultivators said to be the worst kind.

RiCE-PEST OF BRITISH BURMA. 3

external orifices (stigmata) of its tracheae in the cater-
pillar closed and functionally replaced by extensive
series of tracheal-gills or organs for extracting oxygen
from water, and presenting in the pupa stage a
special modification of the cocoon whereby, in a
manner at present not very clearly understood, air is
extracted from the water, and enters the body by three
pairs of the stigmata which at this stage are exceedingly
prominent and, moreover, open. Respiration by means
of the organs termed tracheal-gills (which are nothing
more than fine branches of a closed tracheal system ex-
tended into outgrowths of the surface of the body with
walls so thin and delicate that exchange of gases can
readily take place between the water and the closed
system of tubes), though the rule in several groups of
insects at one or more stages is yet so exceedingly rare
amongst Lepidoptera as to be quite exceptional ; only
two species of this immense order from all parts of the
world having hitherto been shown to possess such organs,
namely, the European Paraponyx stratiotalis, whose
habits, structure, and metamorphoses were admirably
described and delineated by the celebrated Swedish
naturalist Baron de Geer* about the middle of the past
century, and the Brazilian Cataclysta pyropalis, which
forms the subject of an interesting and well-illustrated
essay in last year's volume of Wiegmann's Archiv by
onef of the brothers of him whose philosophic researches
in biology have made the already famous name of Miiller
one of the best known to the science of our day. These
two forms, with the Palan Byoo, belong to the family

* Memoires pour servir a l'Hist. des Insectes, 1752, vol. i, pp. 517-54.1,

pl- 37-

t Willi. MCiller-Blumenau, Ueber einige in Wasser lebende Schmet-

terlingsraupen Brasiliens, in Arch. f. Naturgeschichte, 1884, Band i,
pp. 194-21 1, pl. xiv.

4 RICE-PEST OF BRITISH BURMA.

PyralidcB. Other Pyralidce and Crambidce, it is true, have
similar aquatic habits, as, for example, those of the genera
Hydrocampa, Palustra, Pliilampelits, Aceiitropus, but in
none of them are tracheal-gills present ; the explanation
of the absence of these structures probably being that
the species of the genera mentioned have only compara-
tively recently passed from an aerial to an aquatic mode
of life, and that the action of the new environment
upon them has not been sufficiently prolonged to work
those adaptive structural changes it has brought about
in the European, Brazilian, and Burmese insects.

The caterpillars of the European and Brazilian forms
reside, the one beneath a rude shelter formed by itself
out of a small piece of the food-plant fastened by silk
threads to a leaf, the other beneath a much more com-
plex tent-like silken structure of its own spinning. Both,
in correlation with this habit, have the body more or less
depressed, with the tracheal-gill tufts more or less
lateral and horizontally extended and less numerous ; the
Brazilian form having the body much the more depressed
of the two, and the tracheal-gill tufts much the more lateral
and horizontal, much the less numerous, and all reduced
to simple unbranched filaments. In the Burmese form,
on the contrary, the body of the caterpillar has the typi-
cal (subcylindrical) shape of non-aquatic members of the
same family, and the innermost series of tufts higher
up on the back and more vertical than in the European
species, to which in form and structure, as in distributional
area, it comes nearest, and from which it differs in matters
of detail so trifling as to be at most of specific value ;
whence it may, with tolerable confidence, be inferred that
the Burmese form does not possess the shelter-building
instinct (which, by the way, is not yet quite perfectly
fixed in the European form), but that it crawls free and
uncovered in the midst of the water over the submerged

RICE-PEST OF BRITISH BURMA. 5

stems and leaves of its food-plant, and whence also it is a
permissible, if not in the present state of our knowledge
a probable, suggestion, that the Burmese species is the
living representative of the ancestral form common to
the three.

Paraponyx ORYZALIS, n. sp.

The Caterpillar. Fig. 1.

The caterpillar is about 7 millim., or rather more than
\" long. It was, when received, of a pale whitey-brown
colour. It is now red, having been artificially coloured
by me in order to- render its structure more clearly dis-
cernible. When alive it was no doubt protectively co-
loured to match the plants or other objects amongst
which it lived. It is flat ventrally, transversely convex
or arched dorsally, rather broader than high, and slightly
narrowed at the two ends. The head is not directed
horizontally straight forwards, but slopes slightly down-
wards. It bears a few longish and stiff hairs, and five
eyes on each side in a curvilinear series, the concavity
of which is directed outwards ; the eyes of each side
are arranged in two groups, of which one is anterior,
and the other posterior ; the eyes of the former are close
together, three in number, and the two posterior of
them are subequal to one another and larger than the
anterior ; those of the latter are subequal, about equal
in size to the front eye of the front group, and separated
from one another by an interval about equal to that
which separates the anterior of them from the last of
the front group ; all have a black speck at the outer
margin. In addition to the three pairs of thoracic legs,
which are sparsely furnished with stiff sets like those
on the head and body, there are present five pairs of
short abdominal feet or prolegs on the 6th, 7th, 8th, 9th,

6 RICE-PEST OF BRITISH BURMA.

and 1 2th somites respectively. The stigmata of the
2nd, 3rd, and 4th abdominal somites only are clearly
discernible ; they are oval, pale brown, imperforate areae
with a raised ring-like rim. A few symmetrically ar-
ranged stiff setae spring from rimmed areae not unlike the
closed stigmata. They differ widely in appearance from
the soft and delicate structures now to be described.
The whole animal is covered with a perfect forest of soft
and delicate white filaments which, owing to the manner
in which they have been curled and twisted by the
action of the spirit, appear to be in a state of the wildest
confusion, but are in reality arranged in a most definite
and orderly manner. In the first place, the filaments are
arranged in little bundles or tufts ; that is to say, two, three,
or four of them are united at their bases to form a peduncle
or stalk which is continuous with the integument; rarely
a tuft is represented by a single filament. The tufts are
disposed in four longitudinal rows, extending nearly from
one end of the body to the other. Two of these rows
are nearer to the middle line of the back, but not to
one another, than they are to the other two, which
occupy the sides of the body. The former are placed
above the longitudinal line in which the stigmata or
spiracles lie, and are hence supraspiracular, while the
latter lying below this line may be distinguished as the
infraspiracular tufts. Moreover, a still closer examina-
tion reveals the fact that the infraspiracular tufts are not
all inserted on homologous parts, for, while some of them
are attached to the outer ends of the terga of the somites
to which they belong, others are sternal in position : we
may hence subdivide the infraspiracular rows of tufts
into a tergal and a sternal series. So that we have
two tergal series of tufts, one above and the other below
the spiracular line, with one sternal series, on each side of
the body. It is difficult, owing to the complex manner

RICE-PEST OF BRITISH BURMA. 7

in which they have been curled, twisted, and entangled
by the combined action of spirit and of pressure, to deter-
mine their precise direction, but, of the two series of
tergal tufts, the upper appears to have been directed
almost straight upwards, and the lower to have had a slight
inclination outwards, whilst the sternal series projected
more or less directly downwards, in the living caterpillar
Besides the arrangement in longitudinal rows and series
already described, the tufts have a definite arrangement
on the several somites of which the insect's body is
made up : if we examine an abdominal somite, say the
third, carefully, we shall find that there are present two
tufts belonging to the supraspiracular series, and two
belonging to the lower or infraspiracular series of tergal
tufts, and that in each series one of the 1wo tufts lies in
front of the other ; in other words, that there are an anterior
and a posterior supraspiracular, and an anterior and a
posterior infraspiracular tuft, and, further, that there are
two sternal tufts, one at each end, on each side, or 12
tufts to the somite; consequently, if each of the 12
somites of the body were provided with its full comple-
ment of tufts, there would be 12X12=144 tufts in all.
But owing to the suppression of some or all of the tufts on
certain somites at both ends of the body — for instance,
the first somite has no tufts at all, the second and third
want the anterior sternal and the anterior tergal of the
infraspiracular series, and the last the anterior pleural
and all its tergal tufts — the actual number falls much
below this.

The following table showing the distribution of the
tracheal-gill tufts over one side of the body will, it is
hoped, render the foregoing description somewhat more
intelligible : —

8 RICE-PEST OF BRITISH BURMA.

Tracheal-gill formula of Paraponyx oryzalis.

STERNAL TUFTS.

TERGAL TUFTS.

Somites.

InFRASPIRACULAR.

SuPHASPIRACULAR.

Total.

Anterior.

Posterior.

Anterior. Posterior.

Anterior. Posterior.

i

) y. o

+ o

O + O

0 + 0

o

ii

y s o

+ I

O + I

I + I

4

in

+ I

O + I

I + I

4

J r-i

IV

\ o

+ I

I + I

1 + I

5

V

J 0

+ I

I + I

I + I

5

VI

/ E I

+ I

I + I

I + I

6

VII

ome

+ I

I + I

I + I

6

VIII

+ I

1 + I

I + I

6

IX

12 *i

+ I

I + I

I + I

6

X

\< ?o

+ I

1 + I

I + I

5

XI

) ?°

+ ?I

I + I

I + I

5

XII

' o

-4- I

0 + 0

O + O

i

4

+ 11

+ 8 + io

+ 10 + 10 =

53

which X 2 gives 106, the number of tufts on both sides
of the body.

The caterpillar agrees in all essential particulars of
structure and habits with that described more than a
century and a quarter ago by De Geer, being a thoroughly
aquatic pyralid larva which appears to the naked eye to
be covered with a shaggy coat of coarse and transparent
(in spirit specimens milky-white) hair, and crawls over the
submerged leaves of the plant which it infests in the
very midst of the water. De Geer's caterpillar has the
habit of cutting off an oblong piece from the edge of
a leaf which it applies to a hollow of the leaf, fixing
it loosely thereto by means of a few threads of silk,
so that the cavity enclosed between the two applied
surfaces serves to give lodgment to itself. The
upper surface of the leaves of the plant upon which
this insect lives happens to be concave. The insect,
having an instinctive knowledge of this fact, so places

RICE-PEST OF BRITISH BURMA.

9

the detached piece upon the leaf that the upper surface
of the former comes into apposition with the same sur-
face of the latter, and, by thus turning the two conca-
vities towards one another, gains a more spacious shelter.
Secure beneath the bit of green leaf, it devours the leaf,
to which the former is so loosely applied as to give the
freest possible access on all sides to the currents of
aerated water with which it is necessary that its tracheal-
gills should be constantly bathed. In correlation with
this habit, we find that its body is markedly depressed,
and that the tufts of tracheal-gills all occupy the sides
of the body, where, owing to the interval which exists
between the leaf and its bit, these respiratory organs are
completely exposed to the aerating medium without risk
of injury from the pressure of the bit. In the Burmese
insect, on the contrary, the body is scarcely at all de-
pressed, and the tufts are attached much higher up on
the back ; from which facts itmay with confidence be
inferred that the creature constructs no shelter, but
crawls about free and uncovered in the midst of the
water.

In the Brazilian species (Cataclysta pyropalis) lately
described by Dr. Willi. Miiller-Blumenau, the body is
still more depressed, the tufts are quite lateral in position
and reduced to simple and unbranched filaments, and
the shelter is a much more complex structure than in the
European species.

It is worthy of remark that the aquatic caterpillars
which possess no tracheal-gill tufts, and may hence
be inferred to have entered so recently on their water
life that the changed conditions have not had time to
produce the structural rearrangements needed for a
truly aquatic life, live in a sort of case from which water
is entirely excluded, and are no more aquatic animals in
the sense that they are provided with special organs for

IO RICE-PEST OF BRITISH BURMA.

extracting oxygen from water than are the men who
traverse the sea-bed, their heads encased in divers' hel-
mets : they are simply diving case-bearers.

The caterpillars described by De Geer, by Miiller-
Blumenau, and by myself, on the contrary, always are,
and always require to be, immersed in the water, with
which it is of vital importance to them that their bodies
should be completely and continuously bathed.

The Pupa. Figs. 2, 2a, ib.

The pupa is fusiform, being pointed at both ends, ob-
tusely at the anterior and sharply at the posterior end. It
is 9/5 millims. long by 2*25 millims. broad in its widest
part, its length being to its breadth as four to one, and it is
rather broader than high. In colour it is pale brown on the
legs, wings, and antennae, livid brown as to the body and
eyes, in spirit specimens. The antennae, mouth-parts,
legs, and wings are symmetrically folded back upon the
ventral surface in the usual manner, the posterior legs
reaching to a point which lies about midway between the
end of the abdomen and the end of the fifth somite
of this part in the perfect insect, which, in the speci-
mens before me, is almost ready to emerge, having
already separated from the pupa-skin at its posterior
end. The pupa is quite smooth and entirely devoid
of setae, except the pair of stout black ones which
project forwards and outwards from the truncated front
of the head, and are separated from one another by
an interval equal to the length of one of them. Not a
trace remains of the white branched filaments with which
the body of the caterpillar is beset : these were all
cast off by the caterpillar at its last moult; but the stig-
mata of the second, third, and fourth abdominal somites
have undergone a considerable development, and at this
stage form a series of three tolerably prominent nipple-

RICE-PEST OF BRITISH BURMA. i(

shaped projections on each side of the body ; they are cer-
tainly open, and, moreover, the prominences on which
they are seated have, in growing, broken through the walls
of the pupa-skin so as to gain access to the air-chamber
of the cocoon ; their orifices are transversely elongated
dark-brown slits encircled first by a light-brown and then
by a dark-brown ring. The remaining abdominal stigmata
are indiscernible without dissection, and they certainly do
not pierce the pupa-skin.

The pupa of the Burmese species agrees in all essen-
tial particulars with that of the European form, differing
only in its much smaller size, slenderer form, less promi-
nent stigmata (which, moreover, have their mouths di-
rected outwards and upwards, instead of straight out-
wards), and shorter posterior legs.

The pupa of the Brazilian Cataclysta pyropalis has
only the second and third pairs of abdominal stigmata pro-
minent and concerned in pupal respiration, wants the
frontal setae, and differs in other structural details from
both the above.

The Cocoon. Figs. 3, 3^, 3/'.

The cocoon is spindle-shaped, about 12 millims. long
and 2 '5 broad in its widest part in front, length to
breadth 5:1. It is attached to the middle and sides of
a portion of the upper surface of an imperfectly opened
leaf-blade, the opposite sides of which are firmly and
closely pinched together at either end of it, so that the
only one of its sides left exposed to the water is flat and
has the outline of an ellipse sharply pointed at both
ends, but especially at the aboral end (that towards
which the pupa's tail is directed), which is quite acu-
minate. It is composed of whitish silk, and, though
exceedingly tough and close in texture, is yet sufficiently
transparent to permit of the general form and characters

12 RICE-PEST OF BRITISH BURMA.

of the enclosed pupa being seen through its walls with
tolerable facility. There is no interval between the two
layers of which it would appear to be composed ; these,
on the contrary, being so intimately united as barely to
be distinguishable from one another. The last cast skin
of the caterpillar lies shrivelled up into a pellet in the
aboral end of its interior. The pupa does not lie with its
ventral surface directly opposite to the exposed face of
the cocoon, but slightly turned towards the side which is
to its right, and in the closest relation of apposition there-
with, thus leaving, on the side of the interior of the cocoon
to its left, a cavity into which the three nipple-shaped stig-
mata of its left side can be seen, through the transparent
walls of the cocoon, to project freely. Whether this cavity
contains water and the projections on which the stigmata
open give lodgment to a respiratory apparatus, analogous
to that developed in connection with the rectum in the
Libellulidae, for extracting oxygen from water ; or whe-
ther, as is more probable, it contains air, the openings on
the tops of the projections are stigmata leading directly
into the tracheal system, and the membranous walls of
the cocoon permit of gaseous interchange between the
external water and the cavity, my material is neither
sufficiently large nor suitable for determining.

Explanation of the Plate.

Fig. i. — The caterpillar, about four times the natural
size.

Figs. 2, 2a, 2b. — The pupa, in three different positions,
five times the natural size.

Figs. J, ja, jb. — The cocoon, from in front, from the
side, and from behind, respectively, five times the natural
size.

?«.rk»t- & Co*™-' i

I

'

SB Wood-Mason, J.
608 Some account of the 'Pa-,

R5W6 Ian Byoo ' or 'Teindoung Bo'

Ent. (Paraponyx oryzalis) .

£B
6Q8

F.5W6
Int.

J*/{

3 lOflfi DDBSbbSE fl

nhent SB608 R5W6
Some account of the Palan Byoo or Teindo

m

Yil

.'>

I

W*CWLft