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SMITHSONIAN CONTRIBUTIONS TO KNOWLEDGK.

FLORA AND FAUNA

LIYING ANIMALS

BY

JOSEPH LEI.DY, M.D.,

P II I L A D E L I' II I A .

[ACCEPTED FOE PUBLICATION, HECK si HER, 1861.]

V U L . V. • A f, T. 2.

COMMISSION

TO WHICH THIS PAPER HAS BEEN REFERRED.

PROF. J. W. BAILEY.
CHARLES F. BECK, M. D.

JOSEPH HENRY,

Secretary 8. I.

CONTENTS.

PACK

INTRODUCTION .

Influence of parasites in the production of disease
Parasites of Man .

Entozoa Hominis

Ectozoa Hominis .

Entophyta Hominis

CHAPTER I.

DESCRIPTION OF A FLORA WITHIN ANIMALS 17

§ 1. Of the Anatomy of the Intestinal Canal of Julus marginatua 17

1 2. " " Passalus cornutus

§ 3. Description of the Genus and Species of Enterobryus
Enterobryus

1. Enterobryus elegans

2. " spiralis . • 20

3. " attenuatus . . 20
§ 4. History, Structure, etc., of Enterobryus

1. Of the Principal Cell of Enterobryus .

2. Of the Secondary Cells . . 24

3. Of the Pedicle and Mode of Attachment . 26

4. State of Development of Enterobryus in relation to its particular Locality of

Growth .... 27

5. Advantage of the peculiar forms of different species of Enterobryus . 27

6. Reproduction of Enterobryus .

§ 5. Description of the Genus and Species of Eccrina
Eccrina .

1. Eccrina longa . ...

2. Eccrina nionilifonnis

§ 6. History, Structure, etc., of Eccrina .

1. Of the Principal and Secondary Cells . . 30

2. Of the Pedicle of Eccrina .... 32

3. Of the Position of Growth ... 32

4. Of the Development .... 32
§ 7. Description of the Genus and Species of Arthromitus

Arthromitus

1. Arthromitus cristatus .
§ 8. History, Structure, etc., of Arthroiuitus

1. Of the Spores of Arthromitus . . 35

2. Of the Development of the Spores 35

3. Of the Mode of Attachment of the Thallus . 36

4. Of the Particular Locality and Mode of Growth 36

4 CONTENTS. II.

PAGE

§ 9. Description of the Genus and Species of Cladophytum . 37

Cladophytum ...... 37

1. Cladophytum coraatum ..... .37

§ 10. History, Structure, etc., of Cladophytum ....... 37

§ 11. Description of the Gr«nus and Species of Corynocladus

Corynocladus ......

1. Corynocladus radiatus .....

§ 12. History of Corynocladus .....

§ 13. On some Parasitic Phytoid Bodies, the nature of which is obscure .

CHAPTER II.

A FAUNA WITHIN ANIMALS; BEING DESCRIPTIONS OF NEMATOID ENTOZOA FOUND ASSOCIATED

WITH ENTOPHYTA, AND OF OTHERS ALLIED TO THEM . . .41

§ 1. Description of a Species of Ascaris .

1. Ascaris infecta

§ 2. Habits and Anatomy of Ascaris infecta

§ 3. Description of the Genus and Species of Hystrignathus . 44

Hystrignathus

1. Hystrignathus rigidus .....

§ 4. Description of the Genus and Species of Streptostomurn . . . 45

Streptostomum ... 45

1. Streptostomum agile .... 45

2. " gracile ... 46
§ 5. Description of the Genus and Species of Thelastomum 46

Thelastomum ..... 46

1. Thelastomum attcnuaturu .......

47

47

48

48

48

.48

48

§ G. History, Structure, etc., of Streptostomum and Thelastomum . . . .49

CHAPTER III.
UPON PSEUDO-ENTOPHYTA, ETC. . . . .50

INDEX OF SCIENTIFIC NAMES ......... 55

REFERENCES TO THE PLATES AND FIOTTRES 57

2.

a

appcndiculatum

3.

it

labiatum

4.

it

robustuin

5.

1C

brevicaudatum

6.

11

gracile

7.

11

deprcssum

8.

11

laticolle .

INTRODUCTION.

THE recent excellent works by Dujardin,1 Diesing,2 and Robin,3 upon animal and
vegetable parasites of living animals, render another systematic record of the labors
in this field almost superfluous ; and the object of the present memoir is simply to
give the result of a series of observations, commenced several years ago, upon
associated entozoa and entophyta, constituting a flora and fauna within animals.

The existence of entozoa, or of animals living within other species has, from the
most remote time, attracted attention, on account of the peculiarity of their posi-
tion, the unpleasant ideas associated with them, the sufferings they frequently
induce, and the difficulty of explaining their mode of origin.

The entozoa have always constituted the strongest support of the doctrine of
equivocal or spontaneous generation, one which has found distinguished disciples
even to the present time ; but since the days when barnacles were supposed to
originate from the foam of the ocean, and ducks and geese to be developed from
barnacles, this belief has been so weakened by the accumulation of facts, undenied
and undeniable by the supporters of the doctrine, that it bids fair soon to be little
more than an echo of the past.

The existence of vegetable parasites within animals, or of entophyta, from their
minuteness, remained unknown, until the microscope of Leeuwenhoek detected the
algoid filaments of the human mouth ; but it is only within a comparatively recent
period that any large number of distinct parasitic plants has been discovered.

The very great majority of modern observations indicate that entozoa and ento-
phyta are produced from germs derived from parents, and having a cyclical deve-
lopment.

A great difficulty in determining the course of this development, particularly
with entozoa, is, that their various stages of existence are passed under totally
different circumstances; sometimes within one organ and then another of the same
animal; sometimes in several animals; and, at other times, even quite external to
and independent of the animals they infest. If, however, an entozoon preserved
the same form throughout its migrations, the difficulty just mentioned would be

1 Histoire Naturelle des Helminthes, Paris, 1845.
" Systema Helminthum, Vindobonae, 1850.

3 DCS V6getaux qui croissent sur I'hoinme et sur les animaux vivants, Paris, 1847.
2

6 INTRODUCTION. II.

easily overcome; but such is not the case; for the alteration of form is frequently,
and probably always, so great that two successive conditions cannot be recognized
us the same.1

When, however, entozoa have been traced to their highest condition of develop-
ment, they have always been found to possess •well-characterized organs of repro-
duction, and the females contain such multitudes of eggs as to render it no longer
surprising to find intestinal worms so frequently in vast quantities. The ento-
phyta, when fully studied, have been satisfactorily traced to sporules.

Under the circumstances above mentioned, it is very unreasonable even to sup-
pose the necessity of spontaneous generation for animals, which, in such very
numerous instances have been proved to possess as great capabilities of reproduction

1 Thus, almost everybody is familiar with the Gordius, or hair-worm, vulgarly supposed to be a trans-
formed horse-hair. The animal is rather common in brooks and creeks in the latter part of summer and
in autumn, occurring from a few inches to a foot in length. Its color passes through all shades of brown
to black, and it is perfectly hairlike in its form, except that in the wale the tail end is bifurcated, in the
female trifurcated (American species). No one has yet been able to trace the animal to its origin ! The
female deposits in the water, in which it is found, millions of eggs, connected together in long cords. In
the course of three weeks, the embryos escape from the eggs, of a totally different form and construction
from the parents. Their body is only the l-450th of an inch long, and consists of two portions; the
posterior cylindrical, slightly dilated and rounded at the free extremity, where it is furnished with two
short spines; and the anterior broader, cylindrical, and annulated, having the mouth furnished with two
circlets of protractile tentaculae and a club-shaped proboscis. No one has yet been able to determine what
becomes of the embryo in its normal cyclical course. Those which I have observed, always died a few
days after escaping from the egg.

The grasshoppers in the meadows below the city of Philadelphia are very much infested with a species
of Gordius, probably the same as the former, but in a different stage of development. More than half the
grasshoppers in the locality mentioned contain them ; but those in drier places, as in the fields west and
north of Philadelphia, are quite rarely infested, for I have frequently opened large numbers without finding
one worm.

The number of Gordii in each insect varies from one to five, their length from three inches to a foot ;
they occupy a position in the visceral cavity, where they lie coiled among the viscera, and often extend
from the end of the abdomen forward through the thorax even into the head; their bulk and weight are
frequently greater than all the soft parts, including the muscles, of their living habitation. Nevertheless,
with this relatively immense mass of parasites, the insects jump about almost as freely as those not
infested.

The worms are milk-white in color, and undivided at the extremities. The females are distended with
ova, but I have never observed them extruded.

When the bodies of grasshoppers, containing these entozoa, are broken and lain upon moist earth, the
worms gradually creep out and pass below its surface. Some specimens which crawled out of the bodies
of grasshoppers, and penetrated into earth contained in a bowl, last August, have undergone no change,
and are alive at the present time (November, 1852).

In the natural condition, when the grasshoppers die, the worms creep from the body and enter the
earth; for, suspecting the fact, I spent an hour looking over a meadow for dead grasshoppers, and, having
discovered five, beneath two of them, several inches below the surface, I found the Gordii which had
escaped from the corpses.

Some of the worms put in water lived for about four weeks, and then died from the growth of Aclilya
prolifera. What is their cyclical development?

The facts presented in this note serve well to show the difficulties in ascertaining the developmental
history of entozoa.

II. INTRODUCTION. 7

as those .whose c}7clical development is more evident; and it remains for the sup-
porters of the doctrine to present one single direct observation, before even its
probability can be asserted.

To learn fully the nature, origin, and most favorable conditions of entozoic and
entophytic life, we must commence our investigations with a clear view of the
character and conditions of life in general.

An attentive study of geology proves that there was a time when no living
bodies existed upon the earth.

The oblately spheroidal form of the earth, and the physical constitution of its
periphery, indicate that it was once in a molten state.

A progressively increasing temperature in descending into the interior of the
earth beyond the solar influence, with the phenomena of volcanoes, earthquakes,
hot springs, etc., are strong evidences that the central mass of this planet yet
preserves its early igneous condition.

The period which elapsed was incalculably great before the earth-crust upon its
liquid nucleus had sufficiently cooled by the radiation of its heat for living beings
to become capable of existing upon its surface. Not until the temperature had
been reduced below the boiling point of water (212° F.), could life have originated,
for water in its liquid condition is necessary to the simplest phenomenon of life.
It is even highly probable that no living thing appeared upon the earth's surface
until its temperature had fallen below 165°. This ordinarily is the highest point
at which albumen coagulates,1 a substance in the liquid form, probably existent in
all living beings, and essential to the performance of the simplest vital phenomenon.

Living beings, characterized by a peculiar structure and series of phenomena,
appeared upon earth at a definite though very remote period.

Composed of the same ultimate elements which constitute the earth, they ori-
ginated in the pre-existing materials of their structure.

Living beings originate in a formless liquid matter. The first step in organiza-
tion is the appearance of a solid particle. An aggregation of organic particles con-
stitutes the spherical, vesicular, nucleolated, nucleated body, the organic cell, the
type of the physical structure or organization of living beings.

The phenomena which characterize the living being are: 1. Origin, or birth; 2,
nutrition and assimilation; 3, ex u ration ;2 4, development and growth; 5, repro-
duction ; 6, death. These, in the aggregate, constitute life.

The origin or birth of a living being, is the appearance of its first particle,
whether directly from inorganic nature or from a parent. There is a birth to
every organic cell.

1 Vegetable albumen coagulates from 140° to 160° F. ; animal albumen, from 145° to 165°. — Turner's
Chemistry, American edition, pp. 740, 744.

Albumen in the liquid state "on being heated to 140° begins to give indications of coagulating : if the
solution is very dilute, the temperature may be raised to 165° with the occurrence of this change ; and
when present in very small quantity, the albumen may not separate till the fluid boils, or even until the
ebullition has been prolonged for a short time." — Simon's Chemistry of Man, Am. ed. 1846, p. 24.

a Ejcuro, I consume.

8 INTRODUCTION. II.

Nutrition and assimilation are associated in all living actions, being coeval with
the birth of a living being, and ceasing only upon its death.

During life, particles of the living structure become effete, and are removed by
consumption or exuration, through the agency of the oxygen of the atmosphere.
This process has been confounded with that of respiration, a function of especial
organs, the lungs, branchiae, and tracheae, which exist in higher animals only ; it
is really secondary to the more important process of life, exuration. Exuration
occurs in plants as well as in animals; in germination of the seed and in inflorescence
it is very evident. In the growing plant, exuration is usually masked by the pecu-
liar character and activity of the process of nutrition ; but, at night, when the
nutrition of the plant is at rest, the exuration becomes marked in the evolution of
carbonic acid.

Development and growth are definite in each species of living being.

Reproduction perpetuates the structure as well as the species of the living being.

Death commences with life in the destruction of effete molecules of structure; it
is the cessation of all life-phenomena in the individual, or is the last phenomenon
of life.

To live, requires certain indispensable conditions never absent from life ; always
preceding it. These consist of the specific components of the living body together
with the constant presence of water, air, and a definite range of temperature.

The constituent matter of living beings necessarily precedes the phenomena of
life.

Without water there could be no movement to indicate life.

Air is necessary to exuration. No living being is found out of its influence.
The minutest radicle of a plant never penetrates into the earth beyond the access
of air.

The range of temperature necessary to life is between 35° F.1 and 135° F.2

Life cannot exist independently of any one of the above-mentioned conditions.
In very many instances, the removal of certain of the indispensable conditions of
life-action may take place without the destruction of the power of living when
these conditions are restored. Thus, many plants and animals, seeds and eggs,
may be dried ; yet, upon supplying moisture to them, with all the other conditions,
they will again present the characteristic phenomena of life.

The indispensable conditions of life are susceptible of a great variety of modifica-
tion, within a definite range, without its destruction.

Accompanying a variation of the essential conditions of life, is presented the

1 The so-called red-snow, Protococcus nivalis, Agardh., an algous plant of polar and alpine regions,
grows and reproduces only upon thawing snow, though it may be found beneath virgin snow and in a tem-
perature far below zero; nevertheless, in such circumstances it has ceased all activity, and may remain
so for a long period. The plant is remarkably indestructible. I have a specimen contained in melted
snow-water, yet alive and of a red color, December, 1852, which was brought by the enterprising traveller,
Dr. E. K. Kane, U.S.N., from Cape Beverly, latitude 76.10, during the Griunell expedition for 1850-51,
in search of Sir John Franklin.

8 Certain algae grow in thermal springs, of the temperature of 117° F.

II. INTRODUCTION. 9

immense number of specific and individual peculiarities of living beings. The
variation consists in the difference of the relative quantities of the indispensable
conditions required and supplied, in addition to a modifying influence of light,
probably of electricity, and possibly of some other but yet unknown agency.

The absence or presence of light is a highly important modifying condition to
those indispensable to life. With the solar light, we find the green plant, which
constitutes the basis of life with most terrestrial animals. Without it, the green
plant and its dependent animals could not exist, but -another race, now represented
by certain cryptogamia, and the animal denizens of dark caverns, might inhabit
the earth.

A species of plant or animal may be defined to be an immutable organic form,
whose characteristic distinctions may always be recognized by a study of its his-
tory.

Any species may present individual forms not characteristic ; for all, in the pro-
gress of development and course of life, are liable to modification within definite
limits, which cannot be transcended without cessation of action. The original
proposition is, however, not affected, for no one has ever been able to demonstrate
the transmutation of one species into another.

The most ordinary and extensive modifications of species from the characteristic
type are presented by arrests of development. Hence, the necessity of studying
the history or cyclical course of a species in order to be capable of always recog-
nizing it.

A modification of condition beyond the range of specific life-action, must, necessa-
rily, result in the extinction of the species.

The study of the earth's crust teaches us that very many species of plants and
animals became extinct at successive periods, while other races originated to occupy
their places. This probably was the result, in many cases, of a change in exterior
conditions incompatible with the life of certain species, and favorable to the primi-
tive production of others. But such a change does not always satisfactorily explain
the extinction of species.1

Probably every species has a definite course to run in consequence of a general
law ; an origin, an increase, a point of culmination, a decline, and an extinction.
Within this course there may occur, under the influence of ordinary circumstances,
cycles of temporary increase and diminution, until, finally, the entire machine of
life of the species runs down.

The historical period of man is too short to ascertain with certainty whether
such a view be correct, but it appears to be favored by analogy. The power of re-
production is limited in each individual. Plants may be reproduced to an incalcu-
lable extent by cuttings, but ultimately the power to reproduce in this manner

1 Thus, there are numerous instances of species of animals which have become extinct, and their place
supplied by others so closely allied, that it is difficult to comprehend how the exterior conditions for their
existence should be so different; as in the case of the Equus prlmiyenim, E. Amcricanus, &c., which have
given place to the E. caballus, the Bos primiijcniuts, whose place is supplied by the -Bos taurus, the Bison
latifrons by the Bison Amcricanus, &c.

10 INTRODUCTION. II.

becomes exhausted. The perennial plant puts forth phyton after phyton, but the
seed is necessary to its perpetuation. Numerous lower animals are reproduced to a
vast extent by segmentation or allied processes, but ultimately a recurrence to sexual
admixture becomes necessary for the preservation of the species.1 Sexual admix-
ture, limited to a few families of a species, soon ends in their extinction. Finally,
the complex living being, from birth to death, produces an immensity of living or-
ganisms, the organic cells ; but the egg and seed are necessary to insure the species
against extinction.

Living beings did not exist upon earth prior to their indispensable conditions of
action, but wherever these have been brought into operation concomitantly, the
former originated ; and for such an immensity of time and vastness in quantity, have
they existed, that most of the superficial rocks of the earth's crust are composed of
their remains.

The stratum of life has been always subjected to the destructive agency of earth-
quakes, volcanoes, and torrents ; but it is wonderful how soon, under the play of the
life-conditions, the new surface again teems with living beings. Here and there,
upon the wide area of the earth, an igneous rock peeps out as if to observe the
monopoly of life, but even this, in the progress of time, has its steep sides hidden
by lichens and its summit enveloped in verdure.

Of the life, present everywhere with its indispensable conditions, and coeval in
its origin with them, what was the immediate cause ? It could not have existed
upon earth prior to its essential conditions; and is it, therefore, the result of these?

There appear to be but trifling steps from the oscillating particle of inorganic
matter, to a Bacterium ; from this to a Vibrio, thence to a Monus, and so gradually
up to the highest orders of life ! The most ancient rocks containing remains of

1 Instances in favor of this view are numerous; among others, I have met with a striking example in the
case of a worm, to which I have given the name of Stylaria fossularis (Proc. Acad. Nat. Sci. V. 287).
This worm is found abundantly in ditches in the neighborhood of Philadelphia, during warm weather, and is
constantly observed to be undergoing division. Individuals, a third of an inch long, are usually found to
consist of two divisions, and occasionally of three, in various stages of progress towards separation. The
divisions are composed of about twenty-two annulations, each possessed of a pair of fasciculi of five podal
spines and two bristles. The head consists of a large lobe, with a long digit-like appendage, and presents
an eye upon each side of a large mouth. The latter opens into a capacious pharynx, which afterwards con-
tracts into a cylindrical oasophagus, continuous with a well-developed intestine, but within the animal no
trace of a generative apparatus can be perceived.

In the course of a season, a single individual may reproduce some millions simply by segmentation ; but
as cold weather approaches, we find the animal to lose this power — not resulting from the influence of the
cold, but from exhaustion of the power; because, even if the worms be placed in a warm situation, as in the
window of a warm room, where the sun may shine upon the vessel containing them, they are observed to
cease division. The loss of power of this mode of reproduction, is, however, compensated for by another
succession of developments.

The worms grow to an inch in length and are composed of sixty annulations, each being provided with
double the previous number of podal spines. Within the body, an androgynous generative apparatus be-
comes developed; within the ovaries are developed ova, and within the testis, spermatozoa. Two indivi-
duals copulate, eggs contained in bottle-shaped cases are extruded, and ultimately the parent dies.

After some weeks, in a warm situation, the ova are hatched, the young escape and move freely about, and
soon commence to reproduce their numbers by division.

II. INTRODUCTION. 11

living beings, indicate the contemporaneous existence of the more complex as well
as the simplest of organic forms ; but, nevertheless, life may have been ushered
upon earth, through oceans of the lowest types, long previously to the deposit of
the oldest palaeozoic rocks as known to us ! !

The primitive species of living beings which appeared upon earth, and those
which have been successively and periodically produced, must have been the result
of pre-existing natural conditions, or the former alone originated in this manner,
and the latter were the result of their transmutation under the influence of vary-
ing exterior conditions, or all species in all times originated directly through supra-
natural agency.

The last mode, of course, can only be an inference, in absence of all other
facts ; and if living beings did not originate in this way, it follows they are the
result of natural conditions.

Be this as it may, the most prolonged and closest observations, and the most
carefully conducted experiments have not led to the proof of a single instance of
spontaneous or equivocal generation even of one of the simplest of all living beings ;
but, on the contrary, they all lead farther and farther from or entirely disprove it,
and thus involve the whole subject in obscurity.

Schulze1 performed an experiment to test the possibility of equivocal generation
under the play of the indispensable conditions of life, free from access to any pre-
existing vegetable or animal germs.

A glass vessel half filled with a mixture of various dead vegetable and animal
substances in water, was heated to 212° F., so as to destroy any living bodies which
might exist within. To the vessel was then adapted a pair of Liebig's bulbs, one
of which contained sulphuric acid, the other a solution of potassa, and through
these only could the exterior air have access to its interior. The apparatus was
then placed in a window, where it received the full influence of light and the
necessary temperature for the production of life. The air within the vessel was
daily renewed from May until August, by blowing through the sulphuric acid, from
which it could suffer no change, except to be deprived of moisture and organic
particles. During all that time, not even the simplest animal or vegetable forms
were produced, while in an open vessel containing the same mixture, in the same
situation, there were observed on the following day numerous Vibrios and Monades,
and to these were soon added larger animalculae.

This interesting experiment of Schulze, I repeated with three different vessels ;
in one of which was a mixture of ditch-mud and confervas with water ; in a second,
decaying wood with water; 'and, in the third, a clod of earth with growing grass,
earth-worms, and water. Exactly under the same circumstances, they were sup-
plied with fresh air from time to time, from July of 1850 to December of 1851, and
in the end the results were the same as in the experiment of Schulze.

These experiments, however, may not be conclusive ; other conditions may be

1 Notice of the Result of an Experimental Observation made regarding Equivocal Generation. By F.
Selmlze, Berlin. The Edinluryh New Philosophical Journal, vol. xxiii. 1837, p. 165.

12 INTRODUCTION. II.

required ; what might have been the influence of a long-continued current of elec-
tricity, under the same circumstances, upon the mixtures ?

The experiments of Crosse and Weekes, in the production of the so-called Acarus
Crossii, were performed under the least favorable circumstances to the origination
of life, and, although neither an Acarus nor a Homunculus has been created under
the inspection of man, yet ridicule or prejudice should not prevent us from making
every observation and experiment which can bear on the subject, in order that we
may say positively whether living beings do or do not originate from the inorganic
world under natural and still-existing conditions.1

To the present, we are totally unacquainted with the mode of the primitive origin
of living beings !

Each species once in existence, very generally, and probably universally, requires
two distinct elements, denominated sexual, for its perpetuation.

The power of reproduction by segmentation, budding, or the production of
numerous successions of asexual fertile generations is, probably, in all cases limited ;
the species necessarily reverting to sexual admixture for its perpetuation.

The statements of Horkel2 and Schleiden,3 and their followers, that true sexes
do not exist in the phanerogamia have been most amply refuted by the more careful
observations of Amici,4 Hugo von Mohl,5 Carl Miiller,6 Hoffmeister,7 Gasparini,8
Tulasne,9 and others.

Sexual elements have also been detected in most of the cryptogamia, and, in a
little time, will probably be discovered in all. They have been observed in Ferns,10
Mosses,11 and Alga?,12 but not yet among Fungi.

Having thus taken a cursory glance at the laws of life in general, we have next
to consider those especially operating in the production of parasitic life.

Within living beings, i. e. within their cavities or the parenchyma of the organs,

I The experiments of Crosse and "Weekes appear to me exceedingly absurd; for, in the first case, how were
the carbon and nitrogen of the animal body to be derived by the play of a voltaic current upon a solution of
silicate of potassa? If they previously existed in the water, was it not quite as probable that the ova of
Acari were there also? Again, when the solution of ferrocyanide of potassium was made the womb of life
by the electrical current, why could not the embryology of the new being be observed ? An Acarus is a
highly complex animal, presenting a well-developed tegumentary, muscular, and nervous system, and a
digestive, respiratory, and generative apparatus. The gap between the inorganic world and the Acarus is
greater than that between the latter and man !

• Monatsb. d. Berlin. Akad. 1836.

' Archiv f. Naturges. 1837; Nova Acta C. L. C. Acad. Nat. Cur. vol. xix. 1839, p. 27; Grundziige
d. Wissenschaftliche Botanik.

4 Giornale botanico Italiano, An. 2 ; Annales des Sciences Naturelles, Botanique, 1847, t. vii. p. 193.

5 Botanisehe Zeitung, 1847; An. Sc. Nat., Bot, t. ix. 1848.

6 Ibid ' Ibid, and t. xi. 1849.
8 Ibid. • Ibid. t. xii. 1849.

10 Tulasne, ibid. t. xi. p. 5; ibid. p. 114.

II Schimper: llecherches Anatom. et Morpholog. sur Ics Mousses. Strasbourg, 1848. This author
says, page 55: " Maisje tiens le fait qucjamais une mousse ne parvient d la fructification quand el/e se
trouve hors de f influence des organes queje considere comma des organes malts."

12 Thwaitcs, in Annals and Magazine of Natural History, 1847, vol. xx. p. 9; ibid. p. 343; ibid. 1848,
2d ser. vol. i. p. 161.

II. INTRODUCTION. 13

of course all the indispensable conditions of life exist, and consequently we cannot
wonder at their being infested with other living beings adapted to their parasitic
position. Nevertheless, although the conditions of life are necessarily ever present
in living beings, yet these frequently do not contain parasites. There are many
circumstances besides those essential to life in general, which influence the exist-
ence or non-existence of such forms. One of the most important of these circum-
stances is the convenience or ease of access, or of entrance to the living body
infested.

Within the living, closed, organic cell parasites very rarely if ever exist, because
it is liquid matter only which can endosrnose through cell-membrane, and, there-
fore, solid germs cannot enter,1 and hence the unfrequency of true entozoa in
vegetables. Entozoa may and do penetrate through living tissues, but it is entirely
by the mechanical process of boring.

The intestinal canal of animals is most frequently infested by entoparasites
on account of the ease with which their germs enter with the food.

Aquatic«animals are more troubled by entozoa than those which are terrestrial,
because the water affords a better medium of access than the air.

Terrestrial animals, on the other hand, are more infested by ectoparasites because
their covering of hair, wool, and feathers is more favorable to their protection and
reproduction. A low degree of organic activity and slowly digestible food favor
the development of entoparasites, and hence they are more frequent in the rela-
tively sluggish herbivora than in the carnivora. Comparatively indigestible food,
and such as contains but a small proportion of nutritive matter, from its long
retention in the alimentary canal, favors the development of entozoic and entophytic
germs more than that in which the contrary conditions prevail.2

Animals subsisting upon the endosmosed juices of the tissues of other animals,
and of plants, are rarely infested by parasites, as in the case of the hemi-
pterous insects, aphides, etc., because such food is necessarily free from parasites or
their germs. Entozoa themselves, on this account, are not infested.

On the other hand, if the liquid food be open to the air, parasitic germs may be
readily introduced into the animal, as in the case of the common house-fly, which
often contains myriads of a species of Bodo.

Food swallowed in large morsels favors the introduction of attached parasites;
hence these are frequently found in reptiles, and even in birds, which are. among
the vertebrata, of the highest organic activity.

Animals of feeble organic activity using solid food, which is very slowly digested,

1 In some experiments upon the endosmosis of solid matter through organic cell-membrane, I found that
particles of carmine, diffused in water, which I estimated to measure about the 52,000th of an inch, would
no more penetrate the cell-membrane than the largest masses.

a The inhabitants of the United States appear to be less infested with entozoa than those of any other
part of the world. This probably arises to a great extent from the more nutritious character of their
food j even the poorest laborer being daily supplied with abundance of wholesome flesh, producing a tend-
ency to high organic activity, which is unfavorable to parasitic development.
3

14 INTRODUCTION. II.

and contains little nutriment, are rarely free from parasites. This is the case
with the coleopterous insect Passalus, and the myriapod Julus.

Cooking food is of advantage in destroying the germs of parasites ; and hence
man, notwithstanding his liability to the latter, is le?s infested than most other
mammalia. Did instinct originally lead him to cook his food, to avoid the intro-
duction of parasites?

Entozoa are more abundant than entophyta, because the power of voluntary
movement favors them in their transmigrations, and renders them less liable to
expulsion from the intestinal canal.

Influence of Parasites in Hie Production of Disease. — In many animals entozoa and
entophyta are almost never absent, and probably when in their natural habitation,
and few in number, or not of excessive size, are harmless, as observed by Dujardin
in the introduction of his excellent work on Intestinal Worms : " Les helmiuthes
se deVeloppent dans un site qui leur convient, sans nuire plus que les lichens sur
1'ecorce d'un arbre vigoureux. Us ne peuvent devenir nuisibles, gene'ralement, que
par suite d'une multiplication excessive, laquelle semble alors etre une des conse-
quences d'un affaiblissement provenant d'une tout autre cause, d'une mauvaisq ali-
mentation, du sejour dans un lieu froid et humide, etc. : sans cela, les helminthes
naisscnt et meurent dans le corps de leurs hotes, et peuvent paraitre ct disparaitre
alternativement sans inconv^nients."

Many important diseases have been supposed to originate from parasitic animals
and vegetables. The former are not the true entozoa, for these are too large, and
may be detected by the naked eye, but they are considered to be animalculae so
small that they cannot be discovered even with the highest powers of the micro-
scope. But, independent of the fact that the existence of such entities is a mere
suspicion, none of the well-known animalculae are poisonous. At various times, I
have purposely swallowed large draughts of water containing myriads of Monas,
Vibrio, Euglenia, Volvox, Leucoplirys, Paramecium, Vorticella, etc., without ever
having perceived any subsequent effect.

The production of certain diseases, however, through the agency of entophyta, is
no longer a subject of doubt; as in the case of Muscardine in the Silk-worm, the
Mycodenn of Porrigo favosa in Man, etc. ; but that malarial and epidemic fevers
have their origin in cryptogamic vegetables or spores requires yet a single proof.1
If such were the case, these minute vegetables and spores, conveyed through the
air, and introduced into the body in respiration, could be detected. The minutest
of all known living beings is the Vibrio lineola of Miiller, measuring only the
36,000th of an inch, and the smallest known vegetable spore is very much larger
than this, whilst particles of inorganic matter can be distinguished the 200,000th
of an inch in size.

I have frequently examined the rains and dews of localities in which intermit-
tents were epidemic upon the Schuylkill and Susquehanna Rivers, but without
being able to detect animalculge, spores, or even any solid particles whatever. I

1 See an ingenious little work by my distinguished friend Dr. J. K. Mitchell, " On the Cryptogamous
Origin of Malarious and Epidemic Fevers."

II. INTRODUCTION. 15

have examined the air itself for such bodies, by passing a current through clear
water. This was done by means of a bottle, with two tubes passing through a cork
stopper; one tube dipping into the water, the other reaching not quite to its sur-
face. By sucking upon the latter tube, a current of air passed through the former,
and was deprived in its course of any solid particles. Ordinarily, when the atmo-
sphere was still, early in the morning, or in the evening, neither spores nor animal-
cules could be detected. When piles of decaying sticks or dry leaves were stirred
up, or the dust was blown about by the wind, a host of most incongruous objects
could be obtained from the air; none, however, which could be supposed capable
of producing disease.

To assert, under these circumstances, that there are spores and animalculae capa-
ble of giving rise to epidemics, but not discernible by any means at our command,
is absurd, as it is only saying in other words that such spores and animalcula? are
liquid and dissolved in the air, or in a condition of chemical solution. That the
air may be poisoned by matters incapable of detection by the chemist is proved by
the emanations from such plants as the Rhus vernix, Hlppomane mancinella, etc.

Parasites of Man. — The list of described species of parasitic animals and plants
to which man is liable is already a long one, but nevertheless, in different parts of
the world, others will yet be discovered. According to the most authentic sources,
the known species are as follow : —

ENTOZOA HOMINIS.

Filaria medinensis, Ginelin. Subcutaneous areolar tissue.

Filaria bronchialis. Rudolphi. Bronchial glands.

Filaria oculi hwnani, Nordmann. Eye.

Tricocephalus dispar, Rud. Large intestine.

Strongylus gigas, Rud. Kidneys.

Ascaris lumbricoides, Lin. Small intestine.

Ascaris alata, Bellingham. Small intestine. (Ireland.)

Oxyuris vermicularis, Bremser. Rectum.

Spiroptera kominis, Rud. Urinary bladder.

Ancyclostomum duodenale, Dulimi. Small intestine.

Trichina spiralis, Owen. Muscles.

Pentastomum constrictum, Siebold. Small intestine and liver. (Egypt.)

JBothriocephalus latus, Bremser. Intestines.

Teenia solium, L. Small intestine.

T&nia nana, Siebold. Small intestine and liver. (Egypt.)

Monostomum lenlis, Gescheidt. Crystalline lens.

Distomum hepaticum, Abilgaard. Gall-bladder and portal vein.

Distomum lanceolatum, Mehlis. Hepatic duct.

Distomum oculi humani, Gescheidt. Capsule of crystalline lens.

Distomum Jicematobium, Bilharz. Portal Vein. (Egypt.)

Distomum keterophyes, Siebold. Small intestine. (Egypt.)

Tetrastomum renale, Chiaje. Kidney.

Hexatkyridium pinguicola, Treutler. Ovary.

Hexalhyridium venarum, Treut. In the venous blood.

Cysticercus cellulosce, Rud. Areolar tissue of various organs.

Echinococcus polymm-phus, Diesing. Various viscera.

16 INTRODUCTION. II.

ECTOZOA HOMINIS.

Plilhirius inguinalis, Leach. (Crab-louse.)

Pediculus capitis, Nitzsch. (Head-louse.)

Pediculus vestimenti, Nitzsch. (Body-louse.)

Pediculus tabescentium, Burmeister.

Sarcoptes scaliei, Latreille. (Itch-insect.)

Demodex folliculorum, Owen.

Dermanyssus Boryi, Gervais.

Ixodes americanus, De Geer. (Tick.)

Argas persicus, Fischer.

Pulex irrilans, Lin. (Common flea.)

Pulex penetrans, Gmelin. (Chiggo.) South America.

Cimex lectularius, Lin. (Bed-bug.)

Oestrus hominis, Say. South America.

ENTOPHYTA HOMINIS.

Alga of the mouth.

Achorion Schonleinii, Remak. In porrigo favosa.

Achorion Lebertii, Robin. In porrigo scutulata.

Microsporium Audouini, Gruby. In porrigo decalvans.

Mycoderm of Plica Polonica.

Mycoderm of Mentagra.

Mycoderm of Muguet.

Mycodermata of ulcerated and mucous surfaces.

Sarcina ventriculi, Goodsir. Stomach.

Torulaf1 Stomach.

' * I once saw a plant of this kind in great abundance mingled with the Sarcina ventriculi in the liquid
ejected from the stomach of a man.

CHAPTER I.

DESCRIPTION OF A FLORA WITHIN ANIMALS.

THE most extensive associated flora and fauna which I have discovered within ani-
mals exists with wonderful uniformity within the intestinal canal of the Myriapod,
Julus marginatus, Say, and of the Coleopterous insect, Passalus cornutus, Fabricius;
and in order that the position of the parasites in relation to the different portions
of the intestines may be clearly understood, I have considered it proper to give a
short anatomical description of the latter.

§ 1. — OF THE ANATOMY OF THE INTESTINAL CANAL OF JULUS MARGINATUS.

(PLATE VII. Fig. 21.)

The alimentary canal of Julus marginatus, though extending in a straight line
from mouth to anus, is very large and capacious in relation to the size of the ani-
mal, and is in accordance with the nature of the food.

Opening into the pharynx there are six salivary glands (Plate VII.), two of which
are pyriform (a), conglomerate, and cellular in structure, and placed one upon each
side of the oesophagus ; the others are long and tubular (6) .

The oesophagus is pyriform and capacious (c). The proventriculus (d) forms
nearly half the length of the alimentary canal. It is capacious, cylindroid, and
dilates very gradually from its lower third to its termination. Its lower extremity
is constricted into six annuli, of which the last is twice the width of the others.
The mucous membrane of the proventriculus is smooth, ochreous-yellow in color,
and opaque. At the termination of the proventriculus, there open two Hliary
tubes (e), and from it, surrounding the commencement of the ventriculus, is sus-
pended a broad, white, opaque, reticulated band (/), apparently composed like
the rete adiposa of insects.

The ventriculus (g] forming about one-sixth the whole length of the alimentary
canal, is simple, cylindrical, or intestiniform, and is narrower than the proventri-
culus, and stronger. Upon its exterior surface, it presents several slightly tortu-
ous elevated longitudinal lines. Its lining membrane is smooth, and at the
commencement of the organ .is provided with a single transverse row of thin,
quadrilateral corneous plates.

The large intestine (h) commences very abruptly ; at first being nearly twice the
breadth of the ventriculus ; but at its lower half, it gradually decreases to its

18 A FLORA WITHIN ANIMALS. II.

termination in the rectum, where it is as narrow as the ventriculus. Its parietes
present a great number of slight depressions, arranged in quadrangular groups,
which latter form longitudinal rows the whole length of the large intestine.

The rectum (i) is short, elliptical, and presents several narrow internal longi-
tudinal folds or elevated lines, continuous with the longitudinal lines of separation
of the rows of quadrangular groups of depressions of the large intestine.

It is within the ventriculus, the large intestine, and the rectum, that the exten-
sive Julidean flora and fauna are found.

§ 2. OF THE ANATOMY OF THE INTESTINAL CANAL OF PASSALUS CORNUTUS.

(PLATE VI. Figs. 8-10.)

The intestinal canal of Passalus cornutus, in accordance with the nature of the
animal's food, is capacious, and about three times the length of the body.

The oesophagus extends in a straight line as far back as the mesothorax, is
capacious and claviform, gradually widening to its posterior fourth, and then
narrowing to its termination in the procentriculus.

The latter (PI. VI. Fig. 8, a) constitutes about two-thirds of the whole length
of the alimentary canal. It makes several transversely circular convolutions within
the abdomino-thoracic cavity; it is capacious, and, with the exception of its com-
mencement, which is a little dilated, claviform, is nearly uniformly cylindrical
throughout. The mucous membrane of the proventriculus, with the exception of
a small portion of its posterior extremity, is studded pretty closely with white
circular glands, arranged, though not very regularly, in alternating rows ; which,
through the translucent parietes of the organ, give it a white maculated appearance.
At the junction of the proventriculus with the ventriculus open four biliary
tubes.

The ventriculus (Fig. 8, 1 ; Fig. 9), which in Passalus always contains entophytic
forests, makes a sigmoid turn from the left backwards, and to the right side. It
is one-third broader than the proventriculus ; and, for the most part, is constituted
of six longitudinal rows of transversely oval sacculi separated by as many inter-
vening folds or ridges. The sacculi are about twenty in number, in each row,
separated by transverse folds; they open into the interior of the organ (Fig. 10,
a). At the commencement of the ventriculus, upon the left side, there projects
an oval, curved, ccecal 'poucli (Fig. 9, b), apparently formed by the conjunction of
two of the ventricular sacculi, though as large as four of them. Within the ventri-
culus, the lateral borders of the longitudinal folds (Fig. 10, 6), separating the
sacculi, between the transverse folds (c), are thickly set with simple, bidentate, and
tridentate, amber-colored, corneous spines (PI. IX. Fig. 1, d). These are arranged
in two separate and close columns, convergent forwards, and extending backwards
in a straggling manner .between the ventricular sacculi. Besides these spines, the
surface of the mucous membrane is everywhere studded with distant, stiff, corne-
ous, yellow, translucent, hair-like appendages, which, at the edges of the ventri-

II. A FLORA WITHIN ANIiMALS. 19

cular sacculi, are relatively of considerable length, measuring from the 400th to
the 125th of an inch in length, by the 3000th of an inch thick, while the
others measure the 1154th of an inch in length.

At the termination of the saccular structure posteriorly, the lining membrane of
the ventriculus is provided with a single transverse row of six broad, V-shaped
corneous plates (Fig. 10, d), followed, after a short interval at the junction of the
organ with the fecal intestine, by a thin, yellowish, corneous annulus.

The fecal intestine (Fig. 8, c) is cylindrical, narrower, and more strongly mus-
cular than the proventriculus, and performs nearly the complete circuit of the
abdomen in its course to the anus.

§ 3. DESCRIPTION OF THE GENUS AND SPECIES OF ENTEROBRYUS.
ENTEROBRYIJS, LEIDY.

Thallus attached, consisting of a single, very long, tubular cell, filled with
granules and globules, producing at its free extremity one, usually two, rarely
three, shorter tubular cells, and growing at the other end from a relatively short,
cylindroid, amorphous, coriaceous pedicle, commencing with a discoidal surface of
attachment.

1. Enterobryus elegans, LEIDY.

Proc. Acad. Nat, Sci., Phila., iv., 225.

(PLATE I. Fig. 1 ; II. ; III. Figs. 1-14; IV. Figs. 1-25, 28.)

Thallus olive brown, brownish, yellowdsh, or colorless, transparent, cylindrical,
usually somewhat clavate at the free end; at first forming a single spiral turn, and
then proceeding in a straight or gently flexuose curved line to the free extremity.
Pedicle variable in length to that of the thallus, cylindroid, more or less transversely
contorted, finely striated longitudinally, uniformly brownish in color, commencing
in a broad discoidal expansion. Principal cell very long, cylindrical, slightly dilated
at the commencement, and usually more so, or somewhat clavate at the free end.
Penultimate cell cylindrical. Terminal cell shorter than the last, cylindroid, clavate,
curved, obtusely rounded at the extremity.

Whole length, 2 to 3 lines. Length of pedicle ^iVo to T-JT of an inch ; breadth
szW t° the ys^g- of an inch. Breadth of principal cell, the 7£7 of an inch.
Length of penultimate cell, yJ7 to the -fa of an inch; breadth, y^V-j- to ^|7 inch.
Length of terminal cell, T£T to T£7 inch ; breadth, j-fa-Q to ¥^T inch.

Habitation. Parasitic, growing from the basement-membrane of the mucous
membrane of the small and large intestine of Julus marginatus, Say ; and from any
part of the exterior of Ascaris infecta, Streptostomum agile, and Thelastomum attenua-
tum : entozoa infesting the cavities of the viscera, just mentioned.

20 A FLORA WITHIN ANIMALS. II.

9. Entcrobryus spirnlis, LEIDY.

Proc. Acrid. Nat. Sci., Phila., iv., 2-19.

(PLATE I. Fig. 4.)

Thallua brownish, yellowish, or hyaline, cylindrical, forming a single, double, or
triple spiral. Pedicle cylindroid, expanded at base, or elongated conical, not con-
torted, smooth, or faintly striated longitudinally, brownish or yellowish in color.
Principal cell cylindrical, slightly dilated at the extremities or uniform throughout.
Penultimate cell cylindrical. Terminal cell clavate, curved, obtuse.

Whole length, from fV to &V "lcn- Length of pedicle, ^-^ inch ; breadth, ^^^
to T^7 inch. Breadth of principal cell, -rfa-g inch. Length of penultimate
cell, ffa to ¥£7 inch; breadth, T^? inch. Length of terminal cell, T£T to -^
inch ; breadth, •$•£$•$ inch.

Habitation. Attached to the mucous membrane of the small intestine of Jitlus
pmillus.

3. Entcrobryus attcnuatus, LEIDY.

Proc. Acad. Nat. Sci., Phila., iv., 249.

(PLATE I. Figs. 2, 3; PI. III. Figs. 15-17 ; PI. IV. Figs. 26, 27.)

Thallus faintly brownish, yellowish, or hyaline; forming at first a double flexure
or sigmoid curve, and then proceeding in a straight or gentle curvilinear direction
to its free extremity. Pedicle short, cylindroid, campanulate, or conical with a
spreading base, longitudinally striated, simple, occasionally double, uniformly yel-
lowish. Principal cell cylindrical, attenuated at both extremities, or very slightly
and gradually narrowing from the commencement, or uniform throughout; trun-
cated, or obtusely rounded at the free extremity. Terminal cells rare.

Whole length i line to 1 line. Length of pedicle ^^ to ^£7 inch by ^$Vtf to
^-jiV^ inch broad. Diameter of principal cell; at middle, T^VT inch; at sigmoid
curve, s^Vtf inch ; at the free extremity, ^^^ . In other instances, T{^ inch at the
sigmoid portion, and gradually decreasing to -jiV^ inch at the free end. Where
uniformly cylindrical, about the y^^ inch in diameter.

Habitation. Grows from the mucous membrane of the ventriculus of Raeahtt
cornutus.

§ 4. HISTORY, STRUCTURE, ETC. OF ENTEROBRTUS.

I first discovered the genus of entoparasitic plants, Enterolryus, in the small
intestine of Julm marginatus, in the autumn of 1848, but published no account
of it until October of the following year. From its structure, I immediately sup-
posed it to be a plant ; but afterwards, from the constancy of its existence in the
small intestine, and firmness of attachment to the mucous membrane of the latter,
I began to suspect it might be a part of the structure of the viscus in which it was

II. A FLORA WITHIN ANIMALS. 21

found, of the character of villoid appendages. It then occurred to me that if it
were a plant, it would probably be also found upon fragments of the ligneous food
of the animal within the intestine, which, however, was not the case. On the
other hand, I frequently detected it growing from the exterior surface of three
species of nematoid entozoa infesting the alimentary canal of Julns marginatus with
as much constancy as the plant itself. Among several hundred specimens of these
worms, consisting of Ascaris infccta, Streptostomum agile, and Thelastomuni attenu-
atum, which I had obtained from numerous individuals of Julus marginatus, and
preserved in alcohol, I found twenty which had from one to a dozen filaments
of Enterobryus attached to their exterior surface. Since then, I have observed
that on an average about one in twenty of the entozoa will be found to have the
plant growing upon it. In one instance, I found a large individual of Ascaris infecta,
with twenty-three filaments of Enterobryus growing from its surface, which ap-
peared to cause no inconvenience to the animal, as it moved and wriggled about
with all the ordinary activity of the species (PI. VI. Fig. 1).

The plant rarely reaches its full growth upon the entozoa, although its attach-
ment is as firm as upon its ordinary seat, the mucous membrane of the cavity
infested by the worms.

The principal and constant locality of the Enterobryus, and that in which it is
most frequently met with in full development, in Julus marginatus, is at the com-
mencement of the ventriculus (PL VII. Fig. 21, g). Lower down it is not so abund-
ant; nor is it in this position usually of large size. In the large intestine (/i),
especially at the lower extremity, it frequently exists in the greatest profusion,
but always in a very immature condition.

From the constancy of the presence of Enterobryus elegans within Julus margin-
atus, having examined ovfrr one hundred of the latter without finding it absent
even in a single instance, I was led to suspect its existence within other species of
Julus, and accordingly sought for it in Julus pusillus, a species very much smaller
than Julus marginatus. Within this I detected the second and smallest species, the
Enterobryus spiralis.

I found no entozoa within a dozen individuals of Julus pusillus, nor did the
Enterobryus always exist in it ; in several there were only two or three filaments ;
in two others it grew profusely ; and in two it was not at all present.

From the occurrence of two species of Enterobryus in the two species of Julus
examined, I suspected entophyta would be found very commonly among the
Myriapoda. I therefore examined species of Cermatia, Cryptops, Scolopendra,
Geopldlus, &c., but in none of these carnivorous genera did I discover a trace of a
parasitic plant. In two species, however, of another genus of herbivorous Myria-
poda, Polydesmus granulatus, and Polydesmus virginensis, I found two new and dis-
tinct species of entophyta, which I have referred to a different genus from Entero-
bryus, under the name of Eccrina, of which a description Avill follow hereafter.

Pursuing my researches after entophyta among insects next, I found none among
the Hemiptera, nor the carnivorous Coleoptera, but in our most common, largest
4

22 A FLORA WITHIN ANIMALS. II.

herbivorous coleopterous insect, Passalus cornuhis, resembling very much in its
habits the Julus marginatus, and like it, living in decaying stumps of trees, I found
a constant and most extraordinary profusion of vegetation, only equalled by that of
Julus marginatus, among which was the third and very graceful species, the Entero-
bryus attenuatus.

1. Of the Principal Cell of Enterobryus.— (P\. I. Fig. 1, I; 3, 6; 4, c.) This
is a very long, tubular, cylindrical cell, closed at the extremities. The end
attached to the pedicle is set or received into a concavity, and is usually slightly
dilated beyond the general diameter of the cell. (PI. III. Fig. 11, a.} The distal
end is usually more or less dilated or clavate and obtusely rounded (4), or it is
abruptly truncated (17).

In Enterobryus attenuatus (PI. I. Fig. 3) the cell is sometimes narrowed from the
middle towards both extremities; at other times from the sigrnoid flexure towards
the distal end ; but frequently is nearly uniform in its diameter throughout.

The cell-wall is amorphous in structure, thin, coriaceous, strong, flexible, very
slightly elastic, perfectly transparent, usually colorless — always so in yftung speci-
mens— frequently amber-colored, or yellowish or brownish, and occasionally dark
brown. Its thickness is pretty uniform, except at the extremities, where it is
rather thicker than at the sides. Its usual average is about the -§-fa-$ of an inch.

In E. attenuatus, the cell-wall is sometimes twice as thick at the sigmoid flexure
of the thallus as elsewhere; in the former position measuring the ^0r °f an
inch, in the latter the -jTrtarir of an inch. When the distal extremity of the
principal cell has no secondary ones attached, and is truncated, the cell-wall form-
ing the margin of the extremity is increased in thickness sometimes to a triple
extent, and occasionally projects beyond the general outline of the cell (PL III.
Fig. 17, d). In these latter cases, the cell-wall forming* the terminal face of the
truncated extremity of the cell is sometimes so very thin that it appears as if the
permanent cell-wall ceased at the margin of the extremity, and the internal, very
delicate, transparent, colorless, mucoid bounding layer between the permanent cell-
wall and the cell-contents, or the primordial utricle of Hugo von Mohl, protruded
from the open end, resembling the crystal upon the face of a watch (PI. II. Fig. 4, 6;
III. 7). Generally, however, it is observed that the cell-wall at the truncated ex-
tremity, though thin, is sufficiently strong to prevent the appearance described.
In those cases in which the distal end of the principal cell of Enterobryus is clavate,
with or without attached secondary cells, the cell-wall is thicker at that than at
any other portion of the cell.

The cell-contents consist of a hyaline, or occasionally a faint amber-colored
mucoid or albuminoid fluid, or protoplasma, with granules and globules of various
sizes (PL III.).

It is only in the youngest individuals of Enterobryus that the principal cell
usually contains a large quantity of the protoplasma. Ordinarily, at all more ad-
vanced ages, it is distended with fine and coarse granules and large globules, the
intervals only being occupied by a relatively small proportion of protoplasma.

II. A FLORA WITHIN ANIMALS. 23

The granules are more or less minute, transparent, colorless, or occasionally
faintly yellowish, spherical bodies, measuring from a mere point to the -j^-J^ of
an inch in diameter (Fig. 10). They exist in variable quantity within the prin-
cipal cell, usually more or less enveloping the globules, but never to such an extent
as to exclude the latter, although they are themselves sometimes reduced to a few
scattering points among a mass of globules. Usually, they are most abundant at
the bottom or commencement of the cell (Figs. 6, 9), and rapidly diminish towards
the distal extremity of the latter. Sometimes they are abundant at the bottom
(Fig. 6), and do not exist at all near the distal end of the cell (Fig. 4); at other
times they are found at both ends but none in the middle (Figs. 1-3) ; and lastly,
they are occasionally met with towards the distal extremity of the cell only.

These granules somewhat resemble oleaginous particles in appearance; they are
highly refracting, and are more dense than the surrounding protoplasma.

The globules, as I technically designate them, are colorless, transparent, spheri-
cal, polyhedral, or oblong bodies. When spherical, they are always accompanied
by a more or less large quantity of protoplasma and granules (12). When poly-
hedral they exist in large number, and the form appears as an alteration from the
spherical produced by mutual pressure (2, 14). When oblong, their long diameter
is generally parallel to the length of the cell containing them, and ascends to three
or four times that of the transverse diameter, which in such caseg is always that of
the caliber of the cell (PI. II. 4 ; III. 8). Sometimes they are met with transversely
oblong (2), the long diameter equal to the caliber of the cell, the short diameter
always less than the latter, the form being apparently produced by upward pressure.

In size, the globules usually measure from one-sixth to the whole diameter of the
caliber of the containing cell.

Sometimes they exist almost to the entire exclusion of the ordinary granular
matter, or even the intervening protoplasma (PI. II. 1; III. 2, 13, 14). Sometimes
they are of remarkably uniform size in the same cell, though very variable in this
respect in different cells (17); frequently, however, they vary very much in size
within the same cell (PI. II. 4). Occasionally, a single row of large globules distends
the cell nearly throughout its whole length (PI. III. 13) ; at other times, three or
more rows are observed, polyhedral in form, regularly alternating with one another
(17) through the whole course of the tube, if the latter remains uniform in diame-
ter, or cylindrical; should the tube become clavate, or more dilated at the distal
end, it is always attended by an increase in the relative number of globules (4).

In physical structure, the globules appear to be composed of a somewhat viscid,
amorphous, hyaline, albuminoid liquid, inclosed within an immeasurably thin, amor-
phous membrane, apparently a delicate film of coagulated protoplasma, holding a
mass of the same substance in a liquid condition.

Upon the application of a weak solution of iodine in water to the living thallus
of Euterobryus, a movement is observed to take place in the contents of the princi-
pal cell in an upward direction, or towards the distal end, apparently as if the cell-
wall were contracting, and there was less resistance anteriorly than posteriorly, and
the cell-contents were consequently pushed in the former direction. A moment

24 A FLOKA WITHIN ANIMALS. IL

after, however, the movement is reversed, the globules successively burst, and be-
come at first faintly purplish, and afterwards brownish. The protoplasma and
granules are colored a deep or intensely reddish brown.

With nitric acid, and the subsequent addition of aqua ammonia, the cell-contents
become a confused mass of a beautiful amber color.

Solution of iodine, acetic acid, solution of chloride of sodium, aqua ammonia, or
the long-continued action of water, give rise to a destruction of the different parts
of the cell-contents, and causes a general shrinking of the mass from the inner sur-
face of the cell-wall, the whole apparently held together by the continuity of the
primordial utricle, which now presents a shrivelled, faintly granular appear-
ance (IV. 2).

Occasionally, dead individuals of Enteroltryus are met with in which the cell-
contents are observed to have shrunk to two-thirds or even one-third their original
extent, presenting a shrivelled, irregular, granulo-membranous appearance (PI. IV.
1). The ordinary structural elements of the mass have disappeared, and in their
place yellowish, globular, oil-like bodies are found of various sizes, from a granule
up to one-fourth the diameter of the cell, occupying a position within, and exterior
to, the shrivelled primordial utricular mass* (1, c).

No circulatory movement of the character of cyclosis is ever observed in the cell-
contents, nor can #ny molecular movement be perceived. Upon the rupture of a
cell, however, and the escape of its contents, the finer granules exhibit slight
movements of the kind just mentioned (PI. I. I,/).

2. Of the Secondary Cells. — (PI. I. 1, e; 4, d.) In the fully developed Enterobryus
there are usually two secondary cells ; but occasionally there is only one, and very
rarely there are even three.

In Enterobryus attenuatus, I have never been able to detect two secondary cells,
and only in a few instances have I seen one; arising probably from the more rapid
separation of these cells, after their development, in this species than in the others
(PI. III. 15, 16). A rapid separation of the secondary cells would also account for
the truncated appearance of the distal extremity of the principal cell, and the great
thinness of the cell-wall forming the truncated face, which is often observed in
Enterobryus attenuatus, and but rarely relatively in the other two species (17).

Ordinarily, where two secondary cells exist, as in Enterobryus clegans and Ente-
rdbryus spiralis, they are oblong tubular, and the penultimate cell is usually a little
longer, narrower, and more cylindrical than the terminal cell.

The latter is more or less cylindro-clavate, obtusely rounded at the distal end,
and curved.

The contents of the secondary cells are of the same character as those of the
principal cell. They generally contain a very much greater proportion of the
granular matter than the principal cell, and frequently may be observed to be
filled with granules to the exclusion of globules, the reverse of which I have never
seen (PL I. 1).

When a third secondary cell exists, which I have observed in two or three
instances among some thousands of filaments of Enterobryus elegans, two are alike,

II. A FLORA WITHIN ANIMALS. 25

and correspond to the description of the penultimate secondary cell above given,
while the third is like the ultimate one described. When a single secondary cell
exists in the last-mentioned species of Enterdtryus, it has usually the same appear-
ance as the terminal cell of those cases in which two arc found.

In a half dozen instances only, among several thousand filaments of Entero-
bryus attenuatus, have I been able to detect the existence of a secondary cell.
In some cases it was relatively very short and cylindrical, a trifling degree nar-
rower than the principal cell, truncated at its free extremity, concave at the other,
and fitting upon the convex termination of the principal cell, and .entirely filled
with granular matter. In others, the secondary cell was a very little broader or
more bulging than the principal cell, longer than in the former instances, obtusely
rounded at the free extremity, and filled with a hyaline protoplasma, with a few
granules.

The connection of the secondary cells with the principal cell arid with one an-
other is very variable in its appearance in Enterobryus, and indicates that the
former are derived from the latter by a process of division ; or, in other words, it
indicates at least one of the modes of reproduction of the plant to be by division.

The first indication of the separation of a secondary cell from the principal cell
is a faint line corresponding to a plane passing transversely through the contents
of the latter in the vicinity of its distal extremity (PI. IV. 25, c). Examples are
met with in which such a plane exists with the merest trace of a circumferential
contraction of the primordial utricle at the edge of the plane without the slightest
mark of such a character existing in the permanent cell-wall. The cell-contents
above the plane of separation and for some distance below are always more or less
granular, frequently to the total exclusion of globules, although these are frequently
met with within the fully formed secondary cells.

In well developed principal cells of Enterobryus without attached secondary
cells, the free extremity very generally is more or less filled or even distended with
the characteristic globules, and is clavato in form (PL III. 4, 14), but when second-
ary cells are observed in their commencement, they are filled with granular mat-
ter (PI. IV. 18, 21, 24), from which it appeafs the globules within the distal
extremity of the principal cell are converted into granules in the development of
the secondary cells.

I never observed this transformation step by step, but only saw the conditions
which I have just described. In these cases, if the globules are really converted
into granules, it is most probably not by the former being broken up into corre-
sponding masses of the latter, but by a separation of granules more or less rapidly
from the circumference of the globules; for when secondary cells are in course of
development from the principal cell, the distal extremity of the latter always con-
tains more or less granular matter enveloping the globules, which are spherical,
and, relatively to those ordinarily found lower down, small in size.

Following the plane of division of the principal cell-contents in the production
of a secondary cell, examples of Enterdbryus are met with in which the circumfe-
rential contraction before mentioned, existing at the edge of the plane in the

26 A FLORA WITHIN ANIMALS. II.

primordial utricle within the permanent cell-wall, is deeper than in the former

Next succeeds a distinct separation of the material which is to constitute the
contents of the new secondary cell from that of the principal cell, and a thin trans-
parent partition is formed, between the two portions, continuous at its outer margin
with the enveloping primordial utricle (23, c).

It is not until this period that examples of the plant are found in which there
exists an evident constriction in the permanent cell-well corresponding to the
margin of the partition separating the secondary from the principal cell. This
constriction deepens, and continues to advance concentrically until it completely
divides the thin transparent partition formed from the primordial utrical and sepa-
rating the two distinct masses of cell-contents (19), and thus we have formed from
the principal cell a perfect new or secondary cell. In the case of Enterobryus
elegans, upon which the above observations were made, the distal extremity of the
principal cell, after the complete development of secondary cells still remaining in
connection with the former, is obtusely rounded, a little broader than the second-
ary cells, and appears to indicate that these continue their attachment some time
after they are fully formed.

From the truncated appearance of the principal cell being observed so frequently
in Enterobryus attenuatus, I suspect that the secondary cells, after their production,
detach themselves very rapidly, giving rise to the watch-crystal-like appearance of
the free end of the cell, from the thinness of the new membrane continuous at
its circumference with the older, thicker, and stronger permanent cell-wall (PL
III. 17).

In Euterobryus elegam and Enterobryus spiralis, the production of one secondary
cell is rapidly followed, or even accompanied by another, developed from the prin-
cipal cell. In rare cases, even a third cell commences its development from the
principal cell before the detachment of the terminal cell.

3. Of the Pedicle and Mode of Attachment. (PI. II. 4,c; III. G, 9, 11, b.) The
pedicle of attachment of Enterobryus is more or less cylindrical, solid, hard, trans-
parent, amorphous in structure, yellowish or brownish in color, and faintly striated
longitudinally. Its length varies with the age of the plant, and, to some extent,
with the position of attachment.

In the youngest plants it looks like a very slight conical or mound-like elevation
or thickening of the basement-membrane of the mucous membrane from which the
plant grows (PI. II. 3, V). It is colorless, and, in these cases, from its amorphous
appearance, appears to be part of the structure of the basement-membrane.

As the principal cell grows in length the pedicle does so also, and, in a little
time, appears quite a distinct structure from the basement-membrane to which it is
attached. It reaches its greatest degree of development in Enterobryus elegans, and
when the latter is attached to the exterior of entozoa, it becomes much longer than
in the plants growing from the mucous membrane of the intestine in which the
entozoa are found (PI. VI. Q,e; 7, d). Upon an Ascaris infecta, I have observed indi-
viduals of Enterobryus with the pedicle the ^5- of an inch in length, while, in those

II. A FLORA WITHIN ANIMALS. 27

plants growing from the mucous membrane of the intestine it usually does not grow
more than the ¥J7 of an inch in length.

In Enterobryus attenuatus, the pedicle is usually relatively shorter and broader,
and more conoidal than in Enterobryus elegans.

In the latter, with the growth in length of the pedicle, it becomes more or less
transversely contorted.

At its basis of attachment, the pedicle, when full}' formed, is expanded into a
discoidal surface, by which it adheres with very great tenacity to its body of sup-
port, so as to permit rupture of the pedicle, or the principal cell, without detach-
ment of the former.

In the very young thallus of Enterobryus, the principal cell is situated upon the
convex summit of its pedicle, but as the former grows and the latter increases in
length, the summit of the pedicle becomes depressed, and receives the convex com-
mencement of the principal cell in the manner of a ball and socket joint.

The attachment of the principal cell to its pedicle is strong, and it is much easier
to break than to detach them from one another.

In Enterobryus attenuatus, in two instances, I observed the pedicle, twice its usual
size, divided at the summit, and giving connection to two primary cells of the plant
(PI. IV, 27, &). These cases, of course, constituted an abnormal conjunction, such
as is frequently observed throughout the vegetable and animal kingdom.

4. State of Development of Enterobryus in relation to its particular Locality of
Growth. — The most favorable position for the development of Enterobryus is the
commencement of the small intestine, or, more properly, the ventriculus of Juhts,
and the transverse ridges bounding the sacculi of the ventriculus of Passalus. In
Julus, in the position mentioned, Enterobryus may always be found, and, in most
cases, with secondary cells in all stages of development. In Julus marginatus,
lower down in the ventriculus, Enterobryus is frequently met with, but always,
small in size, and but very rarely advanced to such a degree as to produce secondary
cells. Within the large intestine of the same species of Julus, it may often be
observed, more especially at the lower part, in the most extraordinary profusion,
but always in the earlier stages of growth, rarely more than the sixth of a line in
length, and forming a single, simple curved cell with faintly granular contents, and

Occasionally a few small globules (PI. II. 2).

Enterobryus elegans is frequently found attached to any part of the exterior of
the body of the nematoid entozoa of Julus marginatus, even upon the spiculate tail
of Streptostomum or Thelastomum, which has a very little larger diameter than the
plant itself (PI. VI. 1, 2, 4-7; VII. 12, 15). Upon these worms I have never detected
Enterobryus advanced to the stage of development of secondary cells, and its
greatest length upon Ascaris infecta I found reaching to one line, but never so much
upon the more active Streptostomum agile and Thelastomum attenuatum.

I never detected Enterobryus attenuatus growing upon Hystrignathus rigidus, a
nematoid entozoon rarely absent from the ventriculus of Passalus cormt&s-

5. Advantage of the peculiar forms of different species of Enterobryus. — One of the
most beautiful instances of means adapted to an end in view is presented in the

28 A FLORA AVITIIIN ANIMALS. II.

form of Enterobryus. The plant is fixed upon the mucous, membrane of the in-
testinal canal, in which it grows, and from its delicate structure it must be more or
less constantly liable to rupture in the peristaltic movements of the bowels, and
the passage onwards of the food ; but from the spiral arrangement of the thallus
of Enterobryus elegans and Enterobryus spiralis, and the sigmoid flexure of that of
Enterobryus attemtatus, the graceful filiform plants may be elongated or stretched
onwards for a considerable distance without danger of being torn. (See PI. I.)

6. Reproduction of Enterobryus. — It is no doubt the case that Eiderobryus is not
only reproduced by segmentation, but also by spores, although in several thousand
individuals of Enterobryus elegans which I have examined, in over one hundred
and fifty individuals of Julus marginatus, from early spring until late in the
autumn, I am not positively certain that I either observed the formation of the
spores, or the development of the plant from the spore.

The earliest condition in which I have been able to detect Enterobryus elegans,
was in the form of a delicate, transparent, colorless, globular, oval, or ovate vesi-
cle, measuring the ^^V7 of an inch in diameter, or almost the j-^-n of an inch long,
by the T^Vs of an inch broad (PI. IV. 3). The contents consisted of a colorless
protoplasm. When elongated, the poles of the parietes were thickened, and one
end was adherent to the mucous membrane of the viscus in which these bodies
were found.

In the next stage, the young Enterobryus had the form of a delicate, colorless,
oblong, oval cell, the ^-^-^ of an inch long by the -%-fa-s of an inch broad, filled
entirely with a faintly granular substance; or in other instances, with a mixture
of this and globules, or with globules alone, attached by one extremity to a slight
conoidal, pedicular elevation, arising from the surface of support (4-6). From
this period, as it advances in its development, it is usually disposed to grow in a
cylindroid, curved, clavate form, in which state it may be frequently met with
from the size above given to the T^T of an inch in length (8, 10). Having
reached the latter point, it becomes more cylindrical, and up to the ^ of an inch
in length is disposed to grow into a single spiral coil (11).

Generally the cell-contents, from the earliest condition above mentioned, be-
come almost wholly globular; but within the rectum of Julus marginatus, the
contents of the plant-cells retain their granular appearance, occasionally with a
very few globules, until the latest period in which I have observed them.

Occasionally, the young thallus of Enterobryus elegans grows to ^V °f an inch in
length, perfectly straight, cylindro-clavate in form, and filled with globules
(13, 14). Less frequently, it is found constricted somewhere near the middle of
its length, the distal portion broader than the attached (15). More frequently
than in the two last cases, it is found having a sort of geniculate bending at an
obtuse angle in some part of its course, usually below the middle, but occasionally
above it, with the distal portion possessing a greater diameter than the lower por-
tion, whicl^is straight, while the former is often curved, occasionally recurved,
though so^Rimes also straight (17).

The young of Enterobryus attenuates I observed growing within the ventriculus
of the larva of Passalus cornutus, from the T£ ff of an inch to the T-j-^ of an inch in

II. A FLORA WITHIN ANIMALS. 29

length, cylindrical, and straight or gently curved. Very frequently it presents a
slight geniculate bend, occupying a position generally above the upper fourth or
fifth of the thallus. the distal portion being straight or slightly curved, and, most
commonly, narrower than the lower portion, the reverse of what is observed in
the young of Enterobryus elegans. The contents usually consist of globules.

The next entophyte, to which I shall direct especial attention, I have named
Eccrina, a genus closely allied to Enterobryus, to which, probably, most naturalists
would refer it, but which I was led to consider as distinct, first, in the case of Eccrina
moniliformis, which at the distal extremity of the thallus produces a very great
number of globular secondary cells. The Eccrina longa, originally described as a
species of Enterobryus,^ from its also producing numerous secondary cells, though
not globular, I afterwards preferred assigning to Eccrina.

§ 5. DESCRIPTION OF THE GENUS AND SPECIES OF ECCRINA.
ECCRINA, LEIDY.

Thallus attached, consisting of a single very long tubular cell, filled with granules
and globules, producing at its free extremity a succession of numerous globular or
oblong cells, and growing at the other end from a relatively short, cylindroid,
amorphous, coriaceous pedicle, commencing with a discoidal surface of attachment.

1. Eccrina longa, LEIDY.

Proc. Acad. Nat. Sci., v., 35.

(PLATE V. Figs. 1-13.)

Thallus long, filiform, colorless, or brownish, transparent, cylindrical, usually not
holding a constant relation of breadth to the length, forming a simple curve or
single spiral turn, and then proceeding in a straight line or gently flexuose curve to
the free extremity. Pedicle very short, columnar, expanded at the base. Principal
cell very long, uniformly cylindrical. /Secondary cells in various stages of develop-
ment from ten to thirty in number, oblong, or short cylindrical, with obtusely
rounded extremities when completed.

Whole length from 2 to 7 lines. Length of pedicle ^-ffVtf *° TtW °f an inch.
Breadth of principal cell, from ^^W *° the ^T of an inch. Length of secondary
cells, from the -^-^ to the ^^ of an inch.

Habitation. Parasitic, growing in profusion from the mucous membrane of the
posterior part of the intestinal canal of Polydesmus virginiensis.

1 Proc. Acad. Nat. Sci., vol. v., p. 9.

30 A FLORA WITHIN ANIMALS. II.

2. Eccrina inoniliformis, LEIDY.

Proc. Acad. Nat. Sci., v., 35.

Thallus colorless or ambreous, transparent, growing in a double or triple spiral.
Pedicle short. Principal cell cylindrical. Secondary cells in various stages of deve-
lopment, from 20 to 50 in number, globular when fully formed.

Whole length, from 1 to li lines. Breadth of principal cell y^Vtf of an inch.
Diameter of secondary cells, from the y^Vr *° ^ne T^W °f an inch.

Habitation. Parasitic, growing from the mucous membrane of the intestinal
canal of Polydexmus granulatus.

§ 6. HISTORY, STRUCTURE, ETC. OF ECCRINA.

The genus Eccrina I have not had an opportunity of studying with as much
care as Enterobryus, simply because the animals in which it is parasitic are
not so abundant iu the neighborhood of Philadelphia as the species of Julus.
When I first discovered Eccrina moniliformis, I took notes of its appearance, but
deferred figuring it until a more favorable opportunity, which, however, has not
yet arrived ; for I have since not been able to find any other than the young of
Polydesmus granulatus, in which the entophyte, not constantly existing, does not
present the fully developed condition.

To my friend, Professor Baird, then of Carlisle, Pennsylvania, now of the Smith-
sonian Institution, Washington, I am indebted for numerous individuals of Poly-
desmus virginiensis, from which I obtained materials for figures and full descriptions
of Eccrina longa.

This species is remarkable on account of its very great relative length, not only
to the other entophytes described, but also to the animal in which it is parasitic.

The principal cell in both species of Eccrina is almost uniformly cylindrical
throughout, and in Eccrina longa, at its lower part, makes a long sigraoid flexure,
or single spiral turn, as in Enterobryus elegans, while in Eccrina moniliformis, in
union with its secondary cells, it usually makes a double or triple spiral, as in
Enterobryus spiralis.

The breadth of Eccrina longa is not so uniform as that of Eccrina moniliformis, or
the different species of Enterobryus, nor does it usually correspond to the length.
Thus, I have observed filaments 4 lines in length, the y-jVfr °f an mcn in diameter;
filaments of 5 lines, the ^}^ of an inch; a few of 3 lines, only the ^-^^ of an inch, &c.

Eccrina is the most remarkable of the entophyta which I have discovered, be-
cause a full-grown individual exhibits at one view the process of multiplication of
cells by division in the most gradual state of progression.

1. Of the Principal and Secondary Cells. — (PI. V. 1-6.) The description of these
two kinds of cells must be given together, as the contents in the distal extremity
of the one pass gradually into the construction of the other.

The cell-contents consist of the same materials and in the same varying character
as in Enterobryus, except in full-grown individuals, in which, at the distal extremity,

II. A FLORA WITHIN ANIMALS. 31

they are generally granular, often to the exclusion of globules, and are divided into
distinct masses in the course of development into secondary cells.

In Eccrina lonya, the secondary cells in their origin are first observable as relatively
short cylindrical divisions of the cell-contents within the distal extremity of the
principal cell ^6). Their number does not always correspond with the length of
the thallus. Thus, I have observed filaments 3i lines long, with 25 secondary cells;
others of 6 lines, with from 12 to 20 ; some of 7 lines, with from 16 to 30, etc.
Nor is the length of the secondary cells uniform, nor in relation with that of the
thallus (1-4). They vary in the same and in different individuals in this re-
spect. In some individuals they are found increasing in length successively from
the first to the last, indicating a continuance of growth during the process of
development by division from the primary cell. Thus, in an individual of 6 lines
in length, with 24 secondary cells, the first measured the ^fa of an inch in length,
by the jfa of an inch in breadth, and the others very gradually increased in length,
but diminished slightly in breadth to the last, which measured ¥|7 of an inch in
length by the J^TT °f an inca m breadth. In another individual, 5 lines in length
with 12 secondary cells, these were nearly uniform, measuring from T%\-$ to -%fa of
an inch in length by T|^ of an inch in breadth. In another, of 4 J lines with 10 cells,
they all measured T|-g- of an inch in length by -g-^ of an inch in diameter. In
another, of 7 lines with 25 secondary cells, the first measured ^^u of an inch in
length, the fourth only -^J^ of an inch, and the last ¥|^ of an inch.

The contents of the secondary cells, from their earliest condition, are uniformly
granular (l,c; 2, b; 3, b; 4, a), and in niass appear white and opaque. The granules
are distinct, spherical, transparent, and colorless, and measure from -j-g-J-j-j- to
ysVo" of an inch in diameter. I never observed globules within the attached
secondary cells, but have seen them within those which have become detached,
which will be again referred to (6, a).

The contents of the primary and secondary cells and the cell-wall, conduct them-
selves, upon the application of chemical reagents, in the same manner as Enterobryus.

In the progressive formation of secondary cells, the first step is the division of
the contents within the distal extremity of the primary cell into separate cylin-
drical masses.

At the circumference of the planes of division, a constriction of the primordial
utricle is very early observable, and sometimes a constriction of the permanent
cell-wall rapidly follows or is almost coexistent, but frequently it does not form
until a late period, as in Enterobryus elegans.

Upon the segmentation of the contents within the distal extremity of the primary
cell in the formation of secondary cells, the inner surface of the permanent cell-wall
appears to become combined or continuous with an extremely thin and delicate
membranous layer occupying the planes of separation of the cylindrical, granular
cell-masses, which I suspect is derived from the primordial utricle, or preferably
from the coagulation of a portion of protoplasma, which has exosmosed from the
interior of the cell-masses, each inclosed within a distinct sac of the primordial
utricle, into the interspace at their extremities. This, I say, I suspect to be the
mode of origin of the partition continuous with the permanent cell-wall between

32 A FLORA WITHIN ANIMALS. II.

the secondary cells ; for when the cell-masses, at an early period of their division,
are made to shrink from one another by the application of acetic acid, an exceed-
ingly delicate, but entire membranous partition is observable, or none at all; and in
no instance could I detect a concentric growth from the inner surface of the per-
manent cell-wall ultimately intended to separate the cell-masses. After the forma-
tion of the membranous partition described, the permanent cell-wall at the boundary
of the former becomes constricted, and the secondary cells are apparently completed
by a splitting of the membranous partition through the advancing constriction of
the permanent cell-wall.

Before complete division of the secondary cells, the permanent cell-wall at the
margin of its constriction above and below, is somewhat thickened (2c), but after-
wards again assumes the general thickness, and the two portions of the divided
partition between the secondary cells are thickened to the extent of the lateral
portion of the cell-wall. Frequently, the secondary cells become detached before
the cell-wall at the end has become as thick as it exists laterally, and in such
cases the circumference of the extremity is indicated by a thickened annulus of
the cell-membrane, while that portion of the latter included within the area of the
annulus, resembles the crystal upon the face of a watch (4, a) ; an appearance, as
before stated, frequently observed at the free extremity of the primary cell of
Enterdbryus attenuatus, and of Enterobryus elegans.

The course of development of the secondary cells of Eccrina moniliformis is the
same exactly as that of Eccrina longa. It is, however, more striking, from the
extraordinary number of cells involved in the process, which exhibit a very gradual
progression from the earliest stage to the fully-developed cells. In this species the
early divisions of the cell-contents within the distal extremity of the primary cell
are transversely oblong, but soon assume the globular form as they successively
approach the free end of the thallus.

The secondary cells of Eccrina, in all their stages, uniformly possess granular
contents.

2. Of the Pedicle of Eccrina. — This has the same structure and mode of attach-
ment as in Enterobrytis, but it is always relatively very short.

3. Of the Position of Growth. — I have found Eccrina growing only from the
mucous membrane of the ventriculus of Polydesmus virginiensis and Pulydesmus
granulatus, especially at its commencement, in which position it reaches its most
perfect development. I never detected Eccrina longa growing upon Thelastomum
lal)iatum, an entozoon of Polydesmus virginiensis.

4. Of the Development. — As in the case of Enterobryus, I have never been able to
observe the process from the spore, but have traced it from a very early condition,
most probably derived from the latter, and also from the secondary cells detached
from the parent plant.

Detached secondary cells of Eccrina longa, are not unfrequently observed in-
termingled with the growing filaments of the mother plants. The form of these
detached cells is like those at the free end of the row of secondary cells still attached
but ripe for separation, that is, oblong, or short cylindrical, with obtusely rounded
extremities. They are filled with uniform granular contents, as in the attached

II. A FLORA WITHIN ANIMALS. 33

cells, or they are found filled with a fainter granular matter and more protoplasm,
apparently as if much of the original granular matter had undergone solution, and
less frequently some are observed containing granular contents mixed with globules.

The secondary cells do not always become detached singly from the parent plant,
for I have occasionally observed two and three clinging together by their extremi-
ties, but separated from the parent (6).

The detached cells exhibit a remarkable disposition to reattach themselves by one
extremity, usually to the mucous membrane of the intestinal canal ; but, in several
instances, I have observed them attached to the sides of a growing thallus (5 c). The
law which determines the detachment of the secondary cells from the parent plant,
to become again attached to some other body is curious and difficult to understand.

Besides detached secondary cells, more frequently young growing thalli of Eccrina
are observed, remarkable for their singular form. These consist of a primary cell
from the -^ of an inch to the i of a line in length, with an abrupt geniculate
bend in some part of its course, the upper and lower portions forming a more or
less obtuse angle with each other (8, 9, 11, 13), The portion below the flexure is
cylindrical and usually straight, but occasionally is slightly curved, or sigmoid,
and measures from 5-5*07 to •j-5;l0-0- of an inch in diameter. The upper or distal
portion is more or less dilated, cylindroid, straight, obtusely round at the end, and
measures from the ^oV^ to the y^ of an inch in diameter.

The bend or flexure occurs at any point below the distal third of the thallus.
Sometimes the lower portion of the latter is twice as long as the upper, when it
looks like an oblong cell supported upon a long footstalk (13) ; in other cases, the
upper portion is four or five times longer than the lower (12).

Occasionally, the young thallus observes a straight course throughout, and is
clavate in form (10).

The contents of the young filaments of Eccrina consist of protoplasma with
faintly granular matter (12), or the same combined with a few globules (10), or
the lower portion of the cell is filled with the former, and the upper portion with
the latter (8, 11) ; or, in rather older individuals, the upper portion is frequently
distended with globules, while the lower contains a mixture of granules and globules
passing gradually into a mass of protoplasma at the lower extremity (13), or the
whole, in still more advanced individuals, is entirely filled with globules with a
very few granules and a small quantity of intervening protoplasma (7).

The attachment of the young of Eccrina, like that of Enterobryus, is upon a
slight conical elevation, apparently part of the structure of the basement-membrane.

§ 7. DESCRIPTION OF THE GENUS AND SPECIES OF ARTHROMITUS.

ARTHROMITIJS, LEIDY.
Proc. Acad. Nat. Sci., iv., 227.

Thallus attached by means of one or more granules, simple, cylindrical, very
long, filamentous, articulate, without ramuli. Arliculi indistinct, with amorphous
contents finally converted into solitary oval sporuli.

34 A FLORA WITHIN ANIMALS. II.

1. Arthromitus eristatus, LEIDY.

Proc. Acad. Nat. Sci., iv., 227.
Arthromilus nitidus, Leidy : ibid., v., 35.

(PiATE II., Fig. 1, i; V. 3, d, 14, 15 ; VI. 5 e; VIII. lf,2d, 3, 4, 5.)

Tliallus very delicate, filamentous, linear, straight or inflected, flexible, colorless,
translucent, obtusely rounded at the free end. Pedicle of attachment one or more
atnber-colored round or oval granules. Articuli indistinct, but becoming well-
marked after the development of the interior sporular body. Spore oval, simple,
faintly yellowish, translucent, highly refractive, usually lying oblique and alter-
nating in position in different articuli. Length from the y-^Tr to the ^ of an inch.
Breadth about the -j^-l-g-g- of an inch.

Habitation. Parasitic, grows from the mucous membrane of the ventriculus and
large intestine of Julus marginatits, and also upon Enterobryus elegans, Ascaris in-
fecta, Streptostomum agile, and T/ielastomum attenuatum ; from the mucous membrane
and its appendages of the ventriculus of Passalus cornutus, and Polydesmus virgini-
ensis, and upon Eccrina longa.

§ 8. HISTORY, STRUCTURE, ETC. OF ARTHROMITUS.

The genus Arthromitus, I first detected growing within the ventriculus of Julus
marginalus. Some time subsequently, I detected much larger filaments of the same
plant, with relatively very distinct articuli, growing within the large intestine of
the same animal, which I supposed to be a distinct species from the former, and,
therefore, described it as such under the name of Arthromitus nitidus. Since then,
within Julus marginatus, Passalus cornutus, and Polydesmus virginiemis, I have ob-
served Arthromitus under a variety of conditions, and in all gradations of size and
development, from the simple, exceedingly minute, inarticulate filament, to a length
of one line, with distinct articuli ; and therefore I cannot, at present, distinguish
more than one species ; and for this, the name is retained which was first proposed.

As just stated, I have observed this entophyte from the condition of an exceed-
ingly minute, delicate, inarticulate filament to a thallus one line long, and dis-
tinctly articulate, and containing within very many of the articuli, sporular bodies.

Frequently, there may be detected, growing with the undoubted thallus of Ar-
thromitus, filaments of the former character ; simple, hyaline, and inarticulate, as
short as the -5-^-$ of an inch, as long as the -^ of an inch, and not more than the
sr&TFTT °f an incn in diameter. With these are intermingled filaments, very faintly
articulated, measuring up to the y^-J^nr of an inch in diameter.

Within the ventriculus of Julus marginatus, this entophyte, when fully deve-
loped, measures from the ^7 to the •%%-$ of an inch in length, by the ^T^T to the
islinr °f an inch in diameter.

Within the large intestine of the same animal, Arthrotnitus appears to reach its

II. A FLORA WITHIN ANIMALS. 35

greatest degree of perfection, attaining dimensions of one line in length by the
of an inch in breadth, with remarkably distinct articuli (PL V. 14, 15).

Within the ventriculus of Passalus cornutus, filaments of the plant often acquire
a length of i of a line, and occasionally even of a J line, with a diameter of the
irJo o of an inch.

The articuli of Arthromitus, excepting when they contain spores, are usually
indistinct, arising apparently from the general amorphous character of the contents
which have the same or very nearly the same refrangibility as the cell-wall.
Their average dimensions are the T7tb^ °f an inch m length by the T^^- of an
inch in breadth. In the variety which grows within the large intestine of Julus
marginatus, the articuli are about the length of the diameter of the filaments, or a
very little longer. In that of Passalus cornutus, they average the y^^tf of an
inch in length.

The filaments of Arthromitus are cylindrical, and only depart from this general
form in the very slight dilatation which often exists in the articuli, giving them a
keg-shaped appearance. The contents of the thallus are always amorphous and
hyaline, never having even the faintest appearance of granules.

Not unfrequently, in the largest variety of Arthromitus, several articuli along
the course of the thallus are contracted into a solid columnar form, not more than
half the diameter of the others (14, c).

1. Of the /Spores of Arthromitus. — These are always observed single within the
articuli. Most frequently, they exist only in the articuli which form the distal
portion of the thallus, but they are also often seen in any part of the length of the
latter, sometimes at intervals of a variable number of articuli containing none;
and occasionally, they exist in all the articuli.

In the largest variety of Arthromitus, in which the character of the sporuli is
best observed, the articulations which contain them are slightly contracted, or have
a little less diameter than the others (15, b).

The position of the sporuli is usually oblique, and they alternate in this direction
in the different articuli ; frequently, they are arranged longitudinally, never trans-
versely. They are elliptical in form, transparent, highly refracting like oil-glob-
ules, of a light amber-color, and are amorphous in structure. On the average, they
measure the i^inr °f an ^nc^ *n length, by the 3-20^7 of an inch in breadth. In
the Arthromitus of Passalus cornutus, they measure the •jTTo'oTr °f an inch in length,
by the ^-J^Tr °f an ^ncn iQ breadth. In the largest variety of the plant, they
measure the y-gVj- of an inch in length, by the y^£o^ of an inch in breadth.

2. Of the Development of the Spores. — This is most readily observed within the
articuli of the largest variety of Arthromitus growing within the large intestine of
Julus marginatus (14, 15). The sporuli appear to originate in a gradual contraction,
condensation, and consolidation of the protoplasmoid contents of the articulations.
Within these, may frequently be observed single oval or clavate, or bent oval or
reniform masses, faintly outlined, and nearly filling their cavity (15, a). The masses
gradually contract to the bulk of the spores, and become distinct, shining, and
highly refracting, and in this condition constitute the fully-developed sporuli (6).

36 A FLORA WITHIN ANIMALS. II.

3. Of (lie Mode of Attachment of the Thallus. — Although the attachment of
Arthromitus is very firm and tenacious, yet the thallus possesses no pedicle like
that of Entcrobryus and Eccrina, but groAvs from granular bodies resembling those
upon which the algoid filaments of the human teeth, and those of other animals,
are based.

The granules of attachment, from which a few filaments start, are often single
or isolated ; but usually there is an aggregation of several granules, from which
grow more or less dense bunches of the plant (3, e; 14, a; VIII. 5). The granules
adhere to their basis of attachment as if cemented. They measure from the ^ -J^T
to the -j^inr °f an iQCn *n diameter; usually appear globular in form, and are
amorphous and amber-colored, and refract light as highly as oil-globules.

4. Of the Particular Locality and Mode of Growth. — Arthromitus may be found
in at least 90 per cent, of cases, within the ventriculus of Julus marginatus, rang-
ing from single isolated filaments to very dense bunches. It grows, in company
with Enterobyrus elegans, from the mucous membrane, especially near the com-
mencement of the organ. When in bunches, or tufts, the filaments spread or radiate
from their central granules of attachment, like a dense tassel held upwards. Oc-
casionally, the bunches are found closely twisted, with their filaments intertwined
and plaited, forming columns, from the -gifo-Q to the -j^Vff of an inch in diameter,
spreading at the summit.

Arthromitus is frequently found growing upon Ascaris infecta, Streptostomum agile,
and Thelastomum attenuatum, upon any part of the exterior surface, but most usually
from the lips of the anal and generative apertures, or the interspaces of the annuli
of the body; these, apparently, being the most favorable resting-places for the
sporuli from which the filaments are developed.

It is also frequently found growing in great profusion upon Enterobryus elegans,
often in dense bunches, covering its summit (PL III. 12), or in a number of con-
centric circles on any part of its length, or radiating from particular points (PI. VI.
1, A). A favorite locality for its growth, upon this species of Enterdbryus, is the
basis of attachment of the pedicle of the latter, or the junction of this with the
primary cell. The youngest individuals of Enterobryus are sometimes so com-
pletely covered with Artfiromitus as to be entirely obscured or hidden from view
(PI. IV. 16, c).

As before mentioned, Arthromitus reaches its highest degree of development in
the large intestine of Julus marginatus ; a curious fact, when we recollect that
Enterobryus elegans, although growing here in greater profusion than in the ventri-
culus, never advances to the formation of secondary cells. In the same relation
to quantity as we find Enterobryus, with its state of development in the two cavities
mentioned, so we also find that Arthromitus, with its greater degree of perfection
in the large intestine, does not grow in dense bunches, as in the ventriculus, but in
a very small number of filaments associated together, frequently in pairs ; two,
four, or eight, often single, very rarely more than eight together.

I have never observed Arthromitus to be parasitic upon the entozoa or Enterobryus,
within the large intestine of Julus marginatus. Arthromitus is found within the
ventriculus of Polydesmus virginiensis, but not in the profusion in which it occurs in

II. A FLORA WITHIN ANIMALS. 37

•

Jalus marginatus. It is also not unfrequently found parasitic upon Eccrina longa,
growing in the same manner as upon Enterobryus elegans.

Within the ventriculus of Passalus cornutus, it grows from any part of the
surface, not so abundantly as in Julus marginatus ; but, nevertheless, profusely
from the hair-like appendages of the cavity, or from the mucous membrane forming
the doublings separating the sacculi of the stomach.

I never observed it parasitic upon Enterobryus attemiatus.

§ 9. DESCRIPTION OF THE GENUS AND SPECIES OF CLADOPHYTUM.

CLADOPHYTVIH, LEIDY.

Thallus attached by means of one or more granules ; filamentous, simple, with
minute lateral ramuli, or branched, inarticulate, amorphous in structure.

1. Cladophytum comatum, LEIDY.

Proc. Aoad. Nat. Sci., Phila., iv., 227.
Cladophytum ramosissimum, Leidy : Ibid., iv., 250.

(PLATE II. Fig. 1 h; PI. IV. Figs. 27 d, 28 /; PI. V. Figs. 3/, 14 e; PL VI. Fig If; PI. VIII. Figs. 1 d,

2C)6,7,8.)

Thallus very delicate, linear, colorless, simple, with very minute ramuli, or very
much branched, with minute ramuli upon the terminal branches. Pedicle of
attachment one or more, amber-colored, spherical, amorphous granules. Length
from the ^|7 to the yV of an inch.

Habitation. — Parasitic, in the same positions with Arihromitus.

§ 10. HISTORY, STRUCTURE, ETC. OF CLADOPHYTUM.

In the preceding description, I have included what I formerly considered to be
two distinct species of Cladophytum, as I have since observed a variety of inter-
mediate forms which indicate them to be the same.

Cladophytum is the most minute of the entophyta which I have distinctly
observed. It is very heteromorphous in its character, and there may probably be
several species ; but the power of the microscope in its present condition is not
sufficient to characterize them.

It always appears colorless, branching, and entirely amorphous in structure.

Frequently, it is found consisting of simple filaments, with minute simple ramuli
from the T£7 to the j-^ of an inch in length, by the ^Tr^Ttr *° the j-j-J-j-u °f an
inch in diameter, growing in more or less dense bunches or tufts (PL VIII. 6). The
ramuli do not measure more than the -$-^-3 to the y^TF °f an incn in length. It
is also commonly observed, more or less branching, from the ^-J¥ to the -fa of an
inch in length (PI. V. 3,/; 14, e). The branches are about the T-^7 of an inch in
6

38 A FLORA WITHIN ANIMALS. II.

diameter, and are provided with very minute, oblique ramuli, about the ^-fa-^ of
an inch in length (PI. VIII. 7).

The thallus of Cladophytum, even at the conjunction of the branches, never
presents the slightest trace of articulation.

Of the development of this plant, or the formation of its spores, I could detect
nothing.

Its mode of attachment is the same as that of Arthromitus.

The granules of attachment measure from the y-gVg- to the -$-£$-§ of an inch, and
often exist in masses the ^7 of an inch in diameter.

Cladophytum grows in all the positions in which Artliromitus is found, and the
smallest variety of the former is sometimes observed even growing upon the largest
variety of the latter. It is found in the most extraordinary profusion within the
ventriculus of Passalus cornutus, attached to the mucous membrane and its hair-
like appendages, (PI. VIII. 1; IX.)

§ 11. DESCRIPTION OF THE GENUS AND SPECIES OF CORTNOCLADUS.
CORYWOCI.ADUS, LEIDY.

Thallus attached by means of one or more granules; filamentous, very compound;
branches thicker than the trunk, without ramuli ; inarticulate, amorphous in
structure.

Corynocladus radiatus,

Proc. Acad. Nat. Sci., Phila., iv., 250.

(PLATE VIII. Fig. 1 e; IX. Fig. 2 e; X. Figs. 1, 2.)

Thallus solitary, or growing in more or less dense bunches. Trunk or main
stem relatively narrow, variable in length, either dividing shortly after its origin
into several principal branches, which subdivide into numerous others, many times
longer and thicker than the trunk, and cylindro-clavate in form, and obtusely
rounded at the extremities, or gradually subdividing into numerous cylindro-
clavate branches, thicker but not longer than the trunk.

Maximum length the ^ of an inch. Breadth of trunk from the y^^ to
the Tsfoir of an inch in diameter. Branches •%$-$ to the T^7 of an inch in length,
by the 7-^^ to the 7^V7 of an inch in breadth.

Habitation. — Parasitic", observed only growing from the mucous membrane and
its appendages of the ventriculus of Rwsalus cornutus.

§ 12. HISTORY OF CORTNOCLADUS.

I have never observed the development of this entophyte, nor anything certain
in regard to the formation of its spores, although I have noticed a frequent appear-
ance of a faint granular substance adhering to the exterior of the clavate branches,
which, under a power of 600 diameters, is indistinctly resolved into the form of
elliptical masses, resembling sporules (PI. X. 2).

II. A FLORA WITHIN ANIMALS. 39

§ 13. ON SOME PARASITIC PHYTOID BODIES, THE NATURE OF WHICH is OBSCURE.

Among the objects which I detected with a good deal of constancy within the
ventriculus of Passalus cornutus, is one which has puzzled me exceedingly. It is
an elongated tubular cellule, attenuated at both ends, which I formerly described,
probably -too hastily, as an entophyte, under the name of Cryptodesma? Up to the
present time, I have not been able to satisfy myself of its true character ; whether
it be really an entophyte, or only the epithelial cells of the ventriculus, elongated
by endosmosis (PL X. 3). One would suppose it to be an easy matter to resolve
this question, but there are many difficulties in the way of its determination. Its
constancy of existence is no objection to its entophytic character, for certain
undoubted entophytes, as Enterobryus altenuatus, Arthromitus, and Cladopliytum,
and an entozoon, Hystrignathus rigidus, are quite as constant in their existence.

The epithelial cells of the mucous membrane are ordinarily in the form of
columnar prisms. The bases of attachment of these I have often very distinctly
observed through the translucent basement-membrane from the exterior ; but
their sides, even at the edge of a section of the mucous membrane, I could never
satisfactorily examine, on account of their being totally obscured by the vast
profusion of Arthromitus, Cladophytum, and Corynocladus ; more particularly,
however, by a peculiar vegeto-granular substance, growing everywhere from the
surface of the membrane. In the larva of Passalus, these cells can readily be
distinguished,, and in this they are observed to be prismoid, and are not altered
by the endosmosis of water, so as to assume the form of the phytoid cells in
question. These latter were always seen detached, usually in groups, or adhering
to masses of granular matter, but were never observed attached to the hair-like
appendages of the mucous membrane.

In structure, they resemble more the cellules of a fungous mycelium, than the
algoid plants previously described, consisting of a delicate tubular cell, usually
somewhat irregular, and inclosing very finely granular contents. Acetic acid does
not dissolve them, nor does it destroy the appearance of epithelia observed through
the basement-membrane.

I have examined numerous individuals of Passalus, to ascertain the true nature
of the bodies described, and sometimes almost concluded they were entophytic
parasites ; at others, that they were really elongated epithelial cells ; and, for the
present, I leave the subject, with the intention of investigating it more closely and
patiently at a future time.

In addition to the entophyta described in the preceding pages, which inhabit
the alimentary canal of Julus marginatus and Passalus cornutus, there is also found
within the ventriculus of these animals a peculiar phytoid substance, which is
worthy of attention.

The surface of the mucous membrane of the ventriculus of Julus marginatus, is

1 Proc. Acad. Nat. Sci., Phila., iv., 250.

40 A FLORA WITHIN ANIMALS. II.

very generally studded, at irregular intervals, with circular or oval plano-convex
patches, from the ^T^TT to the ^{T of an inch in diameter, and the T^VT to the
j-fa-g of an inch in thickness, composed of an exceedingly fine granular substance,
yellowish or brownish in color (PL VIII. 2, a). When the patches are larger, they
are more or less lobulated at the circumference, and have the appearance of being
composed of several smaller ones which have run together.

These patches do not originate in a mere deposit of particles of food upon the
mucous membrane ; and though not composed of organic cells, or their transforma-
tions, but only of the minutest granules, measuring from the -g^^, or even less,
to the CT-J-OT of an inch in diameter, yet their character is phytoid. Truly para-
sitic, they firmly adhere to the mucous membrane, and increase in breadth by
growth at the edges. The latter, from their thinness, give the appearance to the
patches as if they possessed a distinct translucent border.

Sometimes the patches have a faintly radiated appearance, which is especially
distinct at the translucent margin.

Besides these patches, there not unfrequently exist irregularly oval or ovate
bodies attached to the mucous membrane, amorphous in structural appearance,
translucent, of a deep-amber color, and measuring from the T^77 to the -gfa of
an inch long, by the ^VW to the ^^ of an inch in breadth (b). These bodies
often become the .nucleus of growth of the granulo-phytoid patches, and either or
both form a favorable nidus of attachment to Arthromitus and Cladopliytum.
None are ever observed growing upon the exterior of the nematoid entozoa, infest-
ing the ventriculus of Julus marginatus.

Within the ventriculus of Passalus cornutus, the hair-like appendages, which
everywhere cover the surface of the mucous membrane, are constantly more or less
enveloped in a granulo-filamentous phytoid substance. As in the case of the phytoid
patches of the ventriculus of Julus marginatus, this substance is not a mere deposit
of particles of food, but a regular parasitic growth (PI. VIII. l,c; IX. 2, c). Upon
the long hairs (PL VIII. 1, b), which fringe the transverse folds between the
ventricular sacculi, this matter accumulates to the thickness of from the 5oVo to
the T^7 of an inch. When a mass is compressed, it has a faintly radiated appear-
ance from the centrally inclosed hair.

The color of this peculiar phytoid substance is ochreous yellow, passing into
brownish at the surface of the masses (PL IX. 2, c).

Frequently, it is observed accumulated upon the summit, or upon any part of
the length of the hairs (PL IX. 2), into round or oval masses, of a yellowish-brown,
brown, reddish-brown, or light-yellow color, with a more or less thick external
stratum, of a faint-yellowish hue, and radiate appearance.

From the granulo-filamentous phytoid substance a vast profusion of Arthromitus,
Cladophytum, and Corynocladus grow, radiating from the surface of some masses
in every direction, from the summit alone of others, or hanging in festoons, the
whole together presenting a most wonderful appearance, and needing no stretch
of the imagination to perceive the resemblance to a most intricate forest, height-
ened to a very great extent by the natural anatomical arrangement of the ventri-
culus (PL IX. 1).

II. A FAUNA WITHIN ANIMALS. 41

CHAPTER II.

A FAUNA WITHIN ANIMALS; BEING DESCRIPTIONS OF NEMATOID ENTOZOA FOUND
ASSOCIATED WITH ENTOPHYTA, AND OF OTHERS ALLIED TO THEM.

ASSOCIATED with the extraordinary flora of the intestinal canal of Julus margina-
tus and Passalus cornutus, there is also a rich fauna. Within the former animal,
there exist, with a good deal of constancy, the following entozoa : —

1, Gregarina Juli marginati,1 within the proventriculus; 2, Ascaris infecta ; 3,
Streplostomum agile; 4, TJielastomum attenuatum ; 5, Nyctotlierus velox / 6, Bodo
julidis;3 and 7, a species of Vibrio, within the ventriculus and large intestine.

In Passalus cornutus are found : —

1, Gregarimi Passali cornuti* within the proventriculus ; 2, Hystrignathus rigidus,
within the ventriculus.

External to the intestinal canal, and within the abdominal cavity, there is like-
wise found an enormous quantity of a species of nematoid worm, apparently not
fully developed,5 and in the thoracic cavity a second species is occasionally observed.8

The only helminth observed in the intestinal canal of Julus pusillus was a spe-
cies of Gregarina}

The common cockroach, Blatta orientalis, contains within its intestinal canal
several species of animals, frequently in great numbers, and also, according to
Valentin,8 an entophyte which grows from the mucous membrane of the large in-
testine. The same plant, Valentin states, grows within the rectum of Astacus
fluviatilis. He refers it to the genus Hygrocrocis, under the specific name of H. in-
testinalis, and thus characterizes it: " Fila simplicia, tenuissima, prolonga, articulata,
serpentina, apice recta, moniliformia, articulis globosis."

A plant agreeing with this description I have not been able to find in the same
insect, the cockroach, introduced into this country ; but, instead of it, in the same
situation mixed with the contents of the intestine, or growing from its mucous
membrane, or occasionally from the nematoidea infesting the cavity, simple,
inarticulate, amorphous filaments from the ^onr to the ^o^^ of an inch in dia-
meter (PL VII. l,e).

The entozoa of Blatta orientalis are : 1, Vibrio ; 2, Bodo; 3, Nyctotlierus ovalis ;9
4, Gregarina;10 5, Streptostomum gracile; and 6, Thelastomum appendicufatum.

1 Trans. Am. Phil. Soc., x. 237. 3 Ib. x. 244. 3 Ib. 4 Ib. x. 238. 5 Ib. x. 241. " Ib. 243. 7 Ib. 238.
8 JRepert. fur Anat. und Phys., Band 1, S. 110, 1836. Robin : Des Ytgit. qui crois. tur L'Homme,
etc., p. 82, 1847. " Trans. Am. Phil. Soc., x. 244. » Ib. x. 239.

42 A FAUNA WITHIN ANIMALS.

§ 1. DESCRIPTION OF A SPECIES OF ASCARIS.

1. Ascaris iiilecta, LEIDY.
Proc. Acad. Nat. Sci., Pliila., iv., 229.

(PLATE VI. Figs. 1, 2, 6, 7; VII. Figs. 5, 11, 14, 16-20, 22.)

Body nearly cylindrical, attenuated posteriorly, obtusely rounded anteriorly,
white, translucent, with the brownish intestine faintly visible through the in-
tegument; tail long, conoidal, curved, acute ; lobes of the mouth prominent. Buccal
organ (oesophagus) robust pyriform, or oblong and dilated below ; gizzard short,
cordiform; intestine cylindroid, narrowing posteriorly, slightly dilated at com-
mencement; rectum elongated, obpyriform, oblique.

Male relatively more cylindrical, with the posterior extremity incurved (PL VII.
5, a) ; furnished ventrally upon each side anterior to the anus, with a longitudinal
row of four minute conoidal tubercles connected by delicate folds of integument;
tail relatively thicker and shorter, furnished upon its ventral surface with two
minute conoidal tubercles. Penis composed of two equal acinaciform spiculse,
about £ of a line long.

Length 2 lines; breadth at origin of intestine T|^ of an inch; at middle ^{^ of
an inch; just anterior to anus ^^ of an inch. Length of tail from anus -j^ of an
inch.

Female, straight (PI. VII. 5, 5). Generative aperture just posterior to the middle,
prominent. Vagina furnished with a large oblong ovate spermatheca.

Length of adult 3 to 4£ lines; breadth anteriorly T|7 of an inch ; at middle -fa
to g1^ of an inch; posteriorly T|^ of an inch.

Ova oval, -g^-g inch long, by T^^ inch broad.

Especial Habitation. — Found constantly within the ventriculus of Julus marginatus,
occasionally within the large intestine. It is sometimes very numerous, of various
ages and sizes. The males are found in proportion to the females about as one to
eight.

§ 2. HABITS AND ANATOMY OF ASCARIS INFECTA.

This Ascarls is frequently observed clinging by means of the mouth to the epi-
thelial lining of the ventriculus of Julus (PI. VII. 5).

In copulating, the male hangs in a sigmoid curve backwards from the female, the
spiculae of the penis introduced within the vagina of the latter (11).

Anatomy. — The buccal organ is very broad and strongly muscular. Its length is
about the -fa of an inch in the female and about two-fifths less in the male (PL
VI. 1, a; 2, 6).

The gizzard is strongly muscular, and nearly as broad as it is long (l,i; 2, c).

H. A FAUNA WITHIN ANIMALS. 43

The intestine is cylindroid, but narrows very gradually from its slightly dilated
origin to its termination (l,c). Its central position within the cavity of the body
is maintained by means of very delicate filaments which pass from the exterior
surface of the organ to the interior surface of the visceral cavity (6, 7).

The mucous membrane of the intestine is lined with an epithelium composed of
distinct, hexahedral, granular, nucleated, organic cells (1, 2, 6, 7).

The rectum is inverted pyriform, with an elongated narrow neck, passing in an
oblique or slightly curved direction to the anal aperture. It is thinner than the
intestine, and the epithelial cells of its mucous membrane are not so distinctly
visible (6, 6; 7, 6).

To the neck of the rectum and the inner margin of the anal aperture are con-
nected a number of muscular bands, radiating in a convergent manner from the
posterior surface of the visceral cavity.

The generative apparatus (VII. 14), in the female, consists of two long ovarial
tubes, one placed anterior and the other posterior to the position of the generative
aperture. Each tube commences by a coecal extremity, is irregularly cylindrical,
dilatable, tortuous, and performs two small convolutions in its course, and is doubled
one and a half times upon itself and the intestinal canal. Each may be considered
to consist of two portions ; the ovary continuous with the oviduct.

The ovary (14, a) dilates very gradually, from its commencement for two-thirds
of its course, after which it is usually more or less irregular in its capacity, depend-
ing upon the quantity of contents ; but near its termination in the oviduct, it is
usually more or less abruptly narrowed and transversely contorted.

The ova within the ovary, for one-third its length, line the interior surface, in the
form of nucleolated, nucleated, organic cells, polyhedral from mutual pressure.
Advancing towards the oviduct, these cells gradually become larger until they
arrive at the lower half of the ovary, where they are so large as to fill the caliber
of the latter in a single row, and the mass of granular contents increases to such
an extent that the original nucleus or the germinal vesicle of the egg is completely
obscured. The ova in the lower half of the ovary are so compressible and elastic
as to assume any form which may arise from exterior pressure ; usually, this form
is some modification of the oval.

The lower extremity of the ovary is lined with an epithelium, though indistinct
and apparently not concerned in the genesis of ova.

The oviduct commences as an abrupt spheroid or pyriform dilatation (&), and
rapidly narrows into a cylindroid tube or neck, which performs a single short con-
volution, and then passes into a straight very dilatable portion to join its fellow of
the other extremity of the body.

The oviduct is lined from its pyriform commencement with a distinct epithelium,
composed of polyhedral nucleated organic cells. Sometimes it is empty, and is
then contracted to such a degree as to appear like a knotted cylindrical cord, but
when distended with ova, it takes the form in outline of the mass of the latter (c) .

The ova within the oviduct are sufficiently strong and resistant to retain their
oval form.

The uterine tube (e), formed by the conjunction of the oviducts, is cylindroid and

44 A FAUNA WITHIN ANIMALS. II.

strongly muscular, and when contracted, is short, thick, and transversely contorted,
and curves forward to the position of the generative aperture and the sperm atheoa,
or when elongated, is narrow, relatively twice as long as in the other case, doubled
upon itself, and first proceeds backward and then forward to the spermatheca, and is
smooth. Its canal is narrow, closed when at rest, and is capable of transmitting
but a single egg at a time.

The spermatheca (/), is a large oblong or long ovoid receptacle, situated ventrally
and anteriorly to the generative aperture, and is connected at its posterior extrem-
ity by the termination of the uterus and commencement of the vagina, which con-
join at an acute angle to each other.

The vagina (g) curves downward, and terminates in an infundibuliform generative
aperture, surrounded by a thick prominent lip (hj PI. VI. 1, g). The parietes of
the vagina are thick, strongly muscular, and transversely contorted.

The ripe ova are oval (PI. VII. 14, c). The young Ascarides (22) have the same
form as the parents. In them, the generative apparatus is entirely undeveloped.

The testicles (16, V) of the male are long, cylindroid, lobed organs, one upon each
side of the posterior part of the intestinal canal, filled with oval sperm atophori (18).

The spiculae of the penis (19), are equal, scimetar-shaped, and are protruded
immediately posterior to the anal aperture (17, c).

§ 3. DESCRIPTION OF THE GENUS AND SPECIES OF HYSTEIGNATHUS.
IIYSTRH-JVV TIH *, LEIDY.

Body cylindroid, rigid, finely annulated ; anterior annulations, excepting the first,
furnished at their posterior margin with simple spines divergent backward. Oral
annulus a truncated cone; mouth round. Tail pointed. Buccal organ long cylin-
drical ; gizzard pyriform. Generative aperture of the female near the middle of
the body. Ovum oval.

*

Hystrignathiis rigidus, LEIDY.

Proc. Acad. Nat. Sci., Phila., v., 102.

(PLATE VII. 8-10.)

Female. — Body straight, rigid, elastic, cylindrical, white, translucent ; anteriorly
and posteriorly narrowed; anterior 106 annuli, extending a short distance posterior
to the position of the commencement of the ventriculus, furnished at their posterior
margin with 16 simple, conoidal, divergent spines ; anterior spines equal in length
to the width of the annuli, the posterior decreasing to mere points; posterior annuli
of the body indistinct. Oral annulus deeply truncated, conical, naked. Mouth large,
round; pharynx extending through the first two annuli; buccal organ (PI. VII. 9, a)
cylindrical, rounded at the extremities, extending through 56 annuli ; gizzard (b)
pyriform, with a cylindrical neck, narrower than the buccal organ, and a spherical

II. A FAUNA WITHIN ANIMALS. 45

body extending through 12 annul! ; intestine cylindrical, slightly dilated anteriorly,
narrowing posteriorly; rectum elongated, inverted pyriforra. Tail long, narrow,
conoidal, curved. Generative aperture near the middle of the body, slightly pro-
minent.

Measurements. — Length 2 lines ; greatest breadth jfa in. ; tail ^ in. long from
the anus ; anterior spinous portion of the body ^ in. long ; buccal organ -^ in.
long, -^ in. broad; gizzard yi^ in. long, with the breadth of its body ¥^7 in.
Anterior spines ^TsVff i*1- l°ng- Ovum ^{T in. long, ^\^ in. broad.

Habitation. — Found within the ventriculus of Passalus cornutus, adhering by
the mouth to the mucous membrane, most usually within the sacculi, and unless it
be scraped out, may escape detection. Three or four individuals are frequently
found within the short blind pouch at the commencement of the ventriculus. It
exists pretty constantly in numbers of two or three to twenty, rarely more.

Although I have examined over a hundred individuals of Passalus cornutus, I
have never found a single male of Hystrignaihus.

§ 4. DESCRIPTION OF THE GENUS AND SPECIES OF STREPTOSTOMUM.

STREPTOSTOmJM, LEIDT.

Body cylindroid, with relatively few annuli, which are very long and distinct.
Mouth large, circular, without lobes or other appendages ; buccal organ and gizzard
pyriform. Female generative aperture posterior to the middle. Tail very long,
spiculate. Penis consisting of a single spiculum.

I

1. Streptostomum agile, LEIDT.

Proc. Acad. Nat. ScL, iv., 230; and ib. v., 285.

(PLATE VI. Fig. 5 ; VII. 2, 12.)

Female. — Body cylindroid, narrowed at the extremities, anteriorly conoidal,
divided into from 60 to 90 annulations. Oral annulus broad, with a prominent labial
margin; second annulus inflated at its anterior margin. Tail very long, very
straight, or slightly sigmoid, or bent at the distal extremity, linear, spiculate, ensi-
form, acute, shining, but slightly flexible. Mouth round, simple; buccal organ
robust, pyriform, extending through thirteen annuli ; gizzard robust, pyriform, with
its neck subdivided into a distinct subglobular portion, extending to the twenty-
first annulus ; intestine cylindrical, capacious, dilated oval at its commencement ;
rectum inverted pyriform. Generative aperture placed twenty-four annuli anterior
to the anal aperture. Ovary double ; ova oval.

Measurements. — Length of body 1 line ; breadth at commencement of intestine
•j^-g- inch; at middle -fa inch. Tail -^ inch long by -gfa inch broad at the middle.
Buccal organ T^T inch long by ¥|^ inch broad ; gizzard ^7 inch long by ^ TTr inch
broad. Ova T£^ inch long by •%$-$ inch broad.

46 A FAUNA WITHIN ANIMALS. II.

Habitation. — Pound within the large intestine of Julus marginatus, and less fre-
quently within the ventriculus.

2. Streptostomum gracile, LEIDY.

Proc. Acad. Nat. Soi., v., 100 ; ib. v., 285.

SYN. Oxyuris Diesingii, Hamraerschmidt: Isis, 1838, 354, Taf. iv., Fig. 6.

Oxyuris Blattce Orientalis, Hammerschmidt: Naturwissenschaftliche Abhandlungen von HAID-

INGER, I. 284, Taf. x., Figs. 4, 7, 13-15.
Anguillula macrura, Diesing : Systema Helminthum, II. 134.

(PLATE VII. Figs. 6, 7.)

Female. — Body cylindroid, attenuated from the middle anteriorly and posteriorly.
Anterior annuli very long and movable upon one another ; posterior annuli shorter
and not so distinct. Oral annulus short, simple ; second amiulus long, constricted in
the middle. Tail nearly one-third the length of the body, straight or curved, spi-
culate, shining. Mouth round, simple ; buccal organ elongated pyriform, with the
neck cylindroid, dilated at its commencement and middle, extending through ten
annuli ; gizzard with a narrow cylindroid neck and globular body, extending to the
eighteenth annulus; intestine cylindroid, very largely dilated oval at commence-
ment.

Measurements. — Length of body 1 line ; breadth opposite the ventricular dilata-
tion T|^ inch ; greatest do. T^T inch ; just above anus -gfa inch. Tail ^ inch
long by the laV^ mch broad at middle. Buccal organ T|^ inch long ; gizzard
inch long. Ovum oval, -$%-$ inch long, ^T inch broad.

Habitation. — Found within the intestinal canal of Blatta orientalis.

§ 5. DESCRIPTION OF THE GENUS AND SPECIES OF THELASTOMUM.

THELASTOMlIltt, LEIDY.

Body cylindroid, annuli moderately long. Oral annulus papilltcform. Mouth
small, circular, without lobes or other appendages; buccal organ long, cylindrical;
gizzard pyriform. Tail moderately long, spiculate. Penis consisting of a single
spiculum.

1. Tlicla si <>iii 11 in attcmiatiiiii, LEIDY.
Proc. Acad. Nat. Sci., iv., 231 ; ib. v., 285.

(PLATK VI. Fig. 4; VII. 1, 23.

Female. — Body cylindroid, translucent white, shining, attenuated anteriorly from
the commencement of the intestine, divided into from 140 to 160 annulations.
Oral annulus minute, papillaeform ; second annulus small, compressed oval. Tail
very straight, or slightly curved, slender, spiculate, acute. Mouth small, simple ;
its passage extending through two and a half annuli ; buccal organ and gizzard
extending through 55 annulations, the former, very long, cylindrical, rounded at

II. A FAUNA WITHIN ANIMALS. 47

the extremities; the latter pyriform, with a short neck, and narrower than the
buccal organ ; intestine cylindrical, dilated, subcordiform at commencement; rectum
inverted pyriform. Generative aperture 42 annulations anterior to the anal.

Measurements. — Length of body -fc to \ of an inch ; breadth at middle -^ of an
inch. Tail ^ of an inch in length by yoVg- of an inch broad at middle. Buccal
organ i line long by ^|^ of an inch broad ; gizzard T|? of an inch long.

Ova 3^3- of an inch long by •%%-$ of an inch broad.

Habitation. — Found with Streptostomum agile, within the large intestine of Julus
marginatus.

2. Thelastomum appcndieulatum, LEIDY.

Proc. Acad. Nat. Soi., v., 101 ; ib. 285.

SYN. Oxyuris Blattce orientalis, Hammerschmidt : Naturwiss. Abhandl. von HAIDINGER, I. 284, Taf. x.
Figs. 10-12 (male, 8, 9, 20?).

(PLATE VII. Fig. 3.)

Female. — Body cylindroid, translucent white, attenuated anteriorly and poste-
riorly ; divided into from 80 to 90 annulations. Oral and second annulus, as in the
preceding species ; terminal annulus with two short spines projecting backward.
Tail straight, spiculate, one-fourth the length of the body. Mouth small, simple ;
its passage extending to the third annulus ; buccal organ and gizzard extending to
the thirtieth annulation ; the former long, cylindrical ; the latter pyriform ; com-
mencement of the intestine broad, cordiform, becoming cylindroid and sending off
a large diverticulum. Generative aperture 26 annulations anterior to the anal.

Measurements. — Length of body 1 line to -^ of an inch ; breadth at commence-
ment of the ventriculus T-J-T of an inch ; at middle -^ of an inch ; at anus -j^ of
an inch. Tail i of a line long by ¥|¥ of an inch broad at middle. Buccal organ
•5*5- of an inch long ; gizzard ^^ of an inch long. Ovum semi-oval, ^|7 of an inch
in length by ^|^ of an inch broad.

Habitation. — Found with Streptostomum gracile in the intestinal canal of Blatta
orientalis.

3. Thelastomnm labiatnm, LEIDY.

Proc. Acad. Nat. Sci., v. 101 ; ib. 285.

(PLATE VII. Fig. 13.)

Female. — Body cylindroid, transparent, anteriorly and posteriorly attenuated,
divided into 140 annulations, of which the anterior are very strongly marked. Oral
annulus inflated, six-lobed at the margin ; second annulus constricted anteriorly.
Tail straight, spiculate, very nearly half the length of the body. Mouth round,
extending through one and a half annuli ; buccal organ and gizzard extending to
the fortieth annulus ; the former cylindroid ; the latter robust ; intestine at com-
mencement subcordiform.

Measurements. — Length J of a line to ^ of an inch ; breadth ^^u of an inch.
Length of tail ^ of an inch. Buccal organ T£7 of an inch ; gizzard 7^ of an
inch. Ovum oval, 5£T of an inch long by -^fa of an inch broad.

48 A FAUNA WITHIN ANIMALS. H.

Habitation. — Found within the ventriculus and large intestine of Polydesmus
virginiensis.

4. Thelastomum robustnm, LEIDY.

Proc. Acad. Nat. Sci., v., 101 ; ib. 285.

Female. — Body white, cylindrical, narrowed anteriorly and posteriorly, divided
into from 200 to 220 annulations. Oral annulus simple. Tail straight, little more
than one-eighth the length of the body. Mouth round, simple ; buccal organ and
gizzard extending through forty annulations ; intestine largely dilated oval at
commencement. Generative aperture 70 annulations anterior to the anal.

Measurements. — Length of body 2 lines ; breadth at the commencement of the
intestine ^ of an inch ; at middle fa of an inch ; just above the anus -fa of an
inch. Length of tail -fa of an inch ; breadth at middle ifa-^ °f an inch. Buccal
organ -fa of an inch long ; gizzard T|r of an inch. Ovum -gfa of an inch long by
-^•g- of an inch broad.

Habitation. — Intestinal canal of the larva of a lamellicorn coleopterous insect.

•7. Thelastomum brevicaiidatiim, LEIDY.

Proc. Acad. Nat. Sci., v.( 208 ; ib. 285.

Female. — Body cylindroid, anteriorly rapidly narrowing from the commencement
of the intestine, posteriorly abruptly rounded ; with a very short spiculate tail.

Measurements. — Length of body to 2 lines ; breadth at commencement of intes-
tine -fa of an inch; at middle -fa of an inch; just above anus T|^ of an inch.
Length of tail from anus ^u of an inch. Buccal organ fa of an inch long ; gizzard
^fj- of an inch long. Ovum oval, -^fa of an inch long.

Habitation. — Intestine of the larva of Scarabasus relictus.

6. Thelastomuin gracile, LEIDY.

Proc. Acad. Nat. Sci., Y., 285.

Oxyuris gracilis, Hammerschmidt : Isis, 1838, 353, Tab. IV. c-f ; Naturwis. Abhandl. v. HAID. I. 287, Tab.

X. Figs. 21-25.
Anguillula gracilis, Closing: Syst. Helm. II. 133.

7. Thelastomum depressum, LEIDY.

Oxyuris depressa, Hammerschmidt: Isis, 1838, 354, Tab. IV. d. e.

Oxyuris dilatata, Hammerschmidt: Naturwis. Abhandl. v. HAID. I. 287, Tab. X. Figs. 26, 27.

Thelasloma dilatation, Leidy: Proc. Acad. Nat. Sci., v., 285.

Anguillula depressa, Diesing: Syst. Helm. II. 133.

8. Thelastomum laticolle, LEIDY.

Proc. Acad. Nat. Sci., v., 285.

Oxyuris laticollis, Hammerschmidt: Naturwis. Abhandl. v. HAID. I. 288, Tab. X. Figs. 28-34.
Anguillula laticollit, Diesing: Syst. Helm. II. 134.

II. A FAUNA WITHIN ANIMALS. 49

§ 6. HISTORY, STRUCTURE, ETC., OF STREPTOSTOMUM, AND THELASTOMUM.

In Thelastomum, the body is longer, has shorter and more numerous annulations,
and a shorter tail than in Streptostomum. In the former, also, the buccal organ is
relatively very long, and cylindrical, in the latter short and pyriform. In Oxyuris
the body is relatively longer than in either the above, is more shortly and nume-
rously annulated, and has the tail constructed like that of Ascaris, instead of being
straight and spiculate, as in the former genera.

In Ascaris and Oxyuris the tail appears to be formed by the gradual attenuation
of the body posteriorly to a point; in Streptostomum and Thelastomum it has more
the appearance of being a superadded appendage, even in the species Thelastomum
brevicaudatum, which has comparatively a very short tail.

In the two genera last mentioned, the tegumentary envelop of the body is so
transparent that all the interior structures are distinctly visible. The integument
is lined by two layers of muscular fibres, the first transverse, the second and stronger,
longitudinal.

Within the muscular investment, apparently upon one side only, in Strepto-
stomum just posterior to the commencement of the intestine (PI. VII. 2, e), and in
Thelastomum at the termination of the buccal organ (1, e), is an apparent follicle,
communicating with the exterior, and having its bottom connected by means of
radiating bands of fibres to the external surface of the alimentary canal in its
vicinity.

Along the course of the interior ventral surface are situated several other appa-
rently glandular organs (PI. VI. 4, e).

The intimate structure of the alimentary canal presents nothing different from
that given in the account of Ascaris infecta.

A remarkable special peculiarity in the construction of the intestine is observable
in Thelastomum appendiculatum. In all other species of the genus, and in Strepto-
stomum, the intestine is simply cylindroid, straight throughout, and more or less
dilated into different forms at its commencement. In Thelastomum appendiculatum
(PI. VII. 3), the intestine commences by a broad, deeply sinuate cordiform dilata-
tion, which rapidly narrows to a short cylindroid portion and then sends off a
long, capacious, gourd-form receptacle, or diverticulum (d), and afterwards pro-
ceeds backwards to the rectum, and in its course, in the vicinity of the generative
aperture, performs a single short convolution.

The generative apparatus (PI. VI. 4) of Streptostomum and Thelastomum is con-
structed upon the same plan as that of Ascaris infecta, except that there is no sper-
matheca, and the dilatable portions of the oviducts terminate at once in the vagina,
which passes obliquely backward, and ventrally to the generative aperture, (d)

50 PSEUDO-ENTOPHYTA, ETC. II.

CHAPTER III.
UPON PSEUDO-ENTOPHYTA, ETC.

•

TRUE free or unattached entophyta are comparatively rare, within the aliment-
ary canal of animals, because they possess no means of counteracting expulsion
•with the ordinary contents of the bowels. They may, however, not unfrequently
exist where they have a very rapid reproductive power, and are so small that
many escape removal at any single expulsive effort of the organ which contains
them.

The Sarcina ventriculi, Goodsir, is an entophyte of the latter character, which
being very minute, and rapidly reproduced, is not easily expelled from the stomach
under the circumstances in which it is found.

Vibriones, and closely allied but not spontaneously moving filaments, very fre-
quently met with in the intestinal contents of herbivorous animals, are probably
true floating or free entophyta, which by their very great minuteness and energetic
reproductive power are prevented from entire removal from the alimentary canal.

In the study of the vegetable parasites of animals, particularly those of the
intestinal canal, it is necessary to be careful not to confound the tissues of certain
well-known cryptogamic plants, which may serve as food or adhere to the ordinary
food of such animals, with true entophyta. Thus fragments of fungi, confervas,
lichenes, and the spores of these, used as food, or adhering as foreign matter to food
of an ordinary kind, are liable within the intestine to be mistaken for parasites.

In midwinter, I found beneath an old fence-rail, an individual of Acheta nigra, or
large black cricket, within the proventriculus of which were large quantities of what
I supposed at the time to be a free, floating entophyte, resembling in general appear-
ance the ordinary yeast fungus, Torula, but which I now suspect to be an ergot upon
which the animal had fed (PL X. 8). The plant consisted of oblong or oval ve-
sicular bodies, apparently thickened at the poles, and filled with a colorless liquid;
but this appearance more probably arose from the cells being distended with a single
large, transparent, colorless, amorphous globule, which pressed a small existing
amount of protoplasma to each end of the cavity. The cells were single, or in rows
to eighteen in number. Frequently, a single cell of comparatively large size had
an attached pair of cells or rows of cells at one or both ends. Occasionally they
were met with, containing one or two small round hyaline, amorphous nuclei.

The isolated cellules measured from the 7^V^ to the T5V^ of an inch in length

II. PSEUDO-ENTOPHYTA, ETC. 51

by the ^^^ to the g-g1^ of an inch in breadth. The rows measured up to the
of an inch in length.

Of a doubtful character, as an entophyte, are also some vegetable bodies which I
observed floating in a honey-colored liquid of the proventriculus of a larva of
Arctia Isabella, a lepidopterous insect, which I found hybernating beneath a stone
in the early part of the month of January.

These bodies in outline resemble the caudex, with its connected radicles, of certain
phanerogamous plants (PI. X. 26).

The caudex-like portion was irregularly oblong or fusiform, brown in color,
opaque, and measured from the ^-g1^ to the gi- of an inch long, and the TTr£or

to the f-ffV-o °f an incn broad.

The filaments were hyaline, cylindrical, irregular in their course, and branch-
ing. They rarely presented the appearance of a partition, and possessed amor-
phous or very faintly granular contents, with an occasional coarse, isolated granule.
Their diameter was pretty uniformly about the TT J^ of an inch. Mixed with
them, generally separated, frequently attached, were numerous sporuloid bodies,
oblong in form, two or three times as long as they were broad, and having the
same structure as the filaments.

The spores of many cryptogamic plants form a very frequent constituent of the
ordinary contents of the bowels of many animals.

It is not improbable that an occasional new species of cryptogamic plant which
grows externally, but has escaped observation, might be discovered in the exami-
nation of the contents of the intestine of such animals as the earth worms, her-
bivorous myriapoda, herbivorous insects, batrachians, and chelonians.

Among a variety of cryptogamic forms, which I have observed mixed with the
contents of the bowels of a number of animals, are several, which, from the singu-
larity of their appearance and the probable importance of directing attention to a
source which may lead to the discovery of new external plants, I will briefly
notice.

One of these is a long cylindrical articulated body, occasionally found mixed with
the food of Julus, Pulydesmus, Passalus, and Lumbricus. It is purplish-brownish
in color, with from 9 to 14 articulations, slightly constricted at the conjunction of
the latter. The extremities are obtusely angular, or one is prolonged into a sort of
pedicle or foot-stalk, expanded at what is the free end in the specimens. The con-
tents of the articulations consist of a central cylindroid, amorphous, transparent
mass, or one or a few aggregated globules, inclosed in a darker amorphous matter
which appears to be a continuous structure of the cell-wall (PI. X. 4, 5).

The length of these bodies is about the ^^ of an inch by the ^Vir °f an mcn in
breadth. The articulations are equal to the diameter, but are sometimes larger,
up to the 2^3- °f an inch in length.

A second remarkable vegetable organism was observed several times among the
contents of the ventriculus of Passalus cornutus and Julus marginatus. This was
a Gonium-\ik.e body, of a dark olive-brownish color, composed of from nineteen to
twenty-seven articulations arranged in four rows side by side, the two outer uniting
at one end in the form of U, and inclosing the other two, which, in some cases,

52 PSEUDO-ENTOPHYTA, ETC. II.

ceased on a level with the extremities of the arms of the TJ, at others projected two
articulations beyond. The articulations were amorphous in structure, with from
one to four minute, indistinct, nucleolar bodies (PL X. 6, 7).

They measured from the j-fa-$ to the y ^ of an inch in length by the TTV^ *°
the y^Vo' °f an inch iQ breadth, and had a thickness corresponding to the diameter
of the articulations, which, on an average, was about the ^^^ of an inch.

In water, these bodies had a slight lateral oscillating movement.

Another curious body, probably a polyspore, I observed several times mixed with
the food within the ventriculus of Passalus cornutus (PI. X. 13). This was V-formed,
articulated, translucent, and purplish-brown in color, and measured along each
arm upon the outer side about the ¥{j of an inch. It consisted of eight articula-
tions, which were amorphous in structure. The articulation forming the apex was
a small inverted cone, upon the base of which was placed the second articulation
which terminated above in two oblique lateral faces, from each of which projected
in a line three articulations forming the divergent arms of the body. The last
articulation of the latter was long and spine-like.

Some cryptogamic spores, which may be taken into the alimentary canal with
the food of the animal, may there commence their development into a mycelium,
though belonging to plants which grow externally.

Of this character are certain sporular bodies which I have observed frequently
existing among the contents of the cloaca of batrachian animals, the plant of which
only completes its development exposed to the air upon the surface of the expelled
excrement (14-25).

Generally, the sporular bodies, found under the circumstances just mentioned,
are globular, and more or less extended upon one side into a cylindroid or clavate
prolongation (14-21). Each extremity is almost always occupied by a single,
large spherical, oval, or pyriform, hyaline, amorphous body, in the interspace of
which the cell-like sporules are filled with a finely granular protoplasm.

Rarely do these bodies advance in their development within the animal more
than has been just described, but occasionally a branching mycelium is met with,
of small extent, consisting of oblong cellules attached by their rounded extremities
(22). The contents of the cellules consist of a colorless liquid protoplasm, some-
times entirely, but generally occupying one extremity of the cells, while the other
is filled by a mass of fine granular matter, with a small round hyaline, nuclear body.
Exterior to the animals, in the excrement, the vegetable bodies under consideration
form an extensively ramifying, articulated mycelium, which sends up straight fila-
ments into the air, producing at the free extremity one or more rows of oval,
granular, sporular bodies (23). Filaments, also, of the mycelium are not unfre-
quently found, in which comparatively large globular spores have been developed,
apparently by an accumulation of the entire granular matter, as it ordinarily exists,
of a single articulation (24).

All the cryptogamic plants described in the preceding pages are innocent denizens
of, or travellers through, the intestinal canal of animals. But, besides plants of this
character, there are many parasitic fungi of animals which are entirely destructive
to life. Such are the Muscardine, Botrytis bassiana, Balsamo, so injurious to the

II. PSEUDO-ENTOPHYTA, ETC. 53

silk-worm,1 and several species of Splucria and Isaria, which also grow within and
upon insects and their larva1.

These fungi grow with great rapidity within the body of the animal they attack,
not only at the expense of the nutritive liuids of the latter, but, after its death, all
the interior soft tissues appear to be converted into a solid mass of mycelium, from
which arise one or more aerial receptacles of the spores.

I once found a specimen of Gryllo-talpa americana, sitting at the mouth of a
hole beneath a log, apparently in perfect health, but, upon nearer examination,
found it had been so completely invaded by a fungous mycelium that even the joints
of the tarsi were distended with it.

The same kind of fungous substance I have observed distending the bodies of
larvae of several species of our indigenous lepidoptera, and once, also, the larva of a
lamellicorn insect.

Of a closely analogous character is a fungus which I found to be very common in
the seventeen-year locust, Cicada septendecim, under the following circumstances : —

In a number of the female insects, within the vagina and projecting externally,
I frequently observed a moist, white, filamentous substance, which I supposed to
be spermatic matter, but, upon examination, found to be composed of a mycelium,
of fungous filaments (PL X. Figs. 27, 28). Most of these were branching, inar-
ticulate, from the -9 oV'o to the -g-g'W of an inch in diameter, and were filled with a
hyaline protoplasma, with an occasional isolated yellowish granule. Others were
united to several oblong cells, or were continuous with what appeared to be the
original spore, and contained a protoplasma, and hyaline amorphous globules.
With the filaments were intermingled numerous round or oval spore-like bodies,
from the TTVU to the -, -^-^ of an inch in diameter, colorless, and with hyaline
granular contents and one or several nuclei (29).

In the spring of 1851, during the imago appearance of the seventeen-year locust,
among myriads of the insect, several friends and myself found between 12 and 20
specimens, which, though living, had the posterior third of the abdominal contents
converted into a dry, powdery, ochreous-yellow, compact mass of sporuloid bodies.
The caudal appendages and posterior two or three abdominal rings covering the
mass, were loose and easily detached, leaving the fungoid matter in the form of a
cone, affixed by its base to the unaffected part of the abdomen of the insect.

The sporuloid bodies, which constituted the entire mass, were oval or ovate in
form, with a wrinkled surface, and faintly granular contents, and measured from
the ^--gVo- to the ^^ of an inch long, by the ^-^ to the ^5^ of an inch broad.

From the observations thus made upon the fungous disease of the seventeen-year
locust, it is probable the insect is more liable to it than we can have any means of
estimating. The fungus may commence its attack upon the larva of the insect, de-
velop its mycelium, and produce a sporular mass within the active chrysalis, while
ascending and descending its chimney to receive full benefit from the air, and in

1 Eighteen years ago, a younger brother and myself, for our amusement, reared several thousand silk-
worms, among which we often observed and carefully removed what we then called "mouldy silk-worms,"
or "silk-worms affected with the mould disease."
8

54 PSEUDO-ENTOPHYTA, ETC. IT.

this stage destroy many which we, of course, never after see, because we never
seek for them. If the fungus has invaded the insect only to such an extent as
not to destroy organs immediately essential to its life, it may pass through its me-
tamorphosis into the imago, but with the posterior part of the abdomen filled with
a mass of fungous substance, as described above.

The reason of the fungous production being always found in the last-mentioned
situation, arises, probably, from the fact that the access of the sporules to the inte-
rior of the animal is much easier through the generative and anal apertures than
through the more delicate passage of the proboscis.

It is probable that this fungous disease of the seventeen-year locust is one of the
means of maintaining the equilibrium in the aggregate of the life of the species
under existing circumstances.1

1 1 say under existing circumstances, for if these change, the species may be either increased or dimi-
nished, or even extinguished; but has not life in the aggregate ever been fixed in its extent? If so, then
if a species be increased, diminished, or extinguished, the equilibrium of life in the aggregate has still
been preserved by another or several other species having diminished, increased, or primitively originated.

INDEX OF SCIENTIFIC NAMES.

[Synonyms are in Roman.]

ACARUS CROSSH, 12.
ACHETA NIGRA, 50.
ACIILYA PROLIFERA, 6.
ACIIORION LEBERTII, 16.

SCHONLEINII, 16.

ANCYCLOSTOMUM DUODENALE, 15.
Anguillula depressa, 48.
gracilis, 48.

laticollis, 48.

macrura, 46.

ARCTIA ISABELLA, 51.
AROAS PERSICUS, 16.

ARTIIROMITUS, 33, 34, 35, 36, 37, 38, 39, 40.
CRISTATUS, 34.

nitidus, 34.

ASCARIS, 42, 49.

ALATA, 15.

- INFECTA, 19, 21, 26, 34, 36, 41, 42, 49.

LUMBRICOIDES, 15.

ASTACTJS FLUVIATILIS, 41.
BACTERIUM, 10.

BlSON AMERICANUS, 9.

LATIFRONS, 9.

BLATTA ORIENTALIS, 41, 46, 47.
BODO, 13, 41.

JULIDIS, 41.

BOS PRIMIGENIUS, 9.

TAURUS, 9.

BOTIIRIOCEPHALUS LATUS, 15.
BOTRYTIS BASSIANA, 52.
CERMATIA, 21.
CICADA SEPTENDECIM, 53.

ClMEX LECTULARIUS, 16.

CLADOPHYTUM, 37, 38, 39, 40.

COMATUM, 37.

— — — ramosissimum, 37.

CORYNOCLADUS, 38, 39, 40.

- RADIATUS, 38.
CRYPTODESMA, 39.
CRYPTOPS, 21.
CYSTICERCUS CELLULOSE, 15.

DEMODEX FOLLICULORUM, 16.
DERMANYSUS BORYI, 16.
DlSTOMUM H^MATOBIUM, 15.

IIEPATICUM, 15.

HETEROPHYES, 15.

LANCEOLATUM, 15.

OCULI HUMANI, 15.

ECCRINA, 21, 29, 30, 32, 33, 36.

— LONGA, 29, 30, 31, 32, 34, 37.
MONILIFORMIS, 29, 30, 32.

ECHINOCOCCUS POLYMORPHUS, 15.
ENTEROBRYUS, 19, 20, 21, 22, 23, 24, 25, 26, 27,
28, 29, 30, 31, 32, 33, 36.

ATTENUATUS, 20, 22, 24, 25, 26,

27, 28, 32, 37, 39.
ELEGANS, 19, 21, 24, 26, 27, 28,

29, 30, 31, 32, 34, 36, 37.
SPIRALIS, 20, 21, 24, 26, 28, 30.

EQUUS AMERICANUS, 9.

CABALLUS, 9.

PRIMIGENIUS, 9.

EUGLENIA, 14.

FlLARIA BRONCHIALIS, 15.

- MEDINENSIS, 15.

OCULI HUMANI, 15.

GEOPHILUS, 21.
GONIUM, 51.

GORDIUS, 6.'
GREGARINA, 41.

JULI MARGINATI, 41.

PASSALI CORNUTI, 41.

GRYLLO-TALPA AMERICANA, 53.
HEXATHYRIDIUM PINGUICOLA, 15.

VENARUM, 15.

HlPPOMANE MANCINELLA, 15.
SYGROCHOCIS, 41.

— INTESTINALIS, 41.
HYSTRIGNATHUS, 44, 45.

- RIGIDUS, 27, 39, 41, 44.
ISARIA, 53.
IXODES AMERICANUS, 16.

56

INDEX OF SCIENTIFIC NAMES.

II.

JULUS, 14, 27, 30, 42, 51.

- MAIUU.VATI :s, 17, 19, 20, 21, 22, 27, 28,
34, 35, 36, 37, 39, 40, 41, 42, 46, 47, 51.
PUSILLUS, 20, 21, 41.

LEUCOPIIRYS, 14.
LUMBRICUS, 51.
MlCROSPORIUM AUDOUINII, 16.
MONOSTOMTJM LENTIS, 15.
MONAS, 10, 14.
NYCTOTHERUS OVALIS, 41.

: VELOX, 41.

(ESTRUS HOMINIS, 16.
OXYURIS, 49.

Blattas orientalis, 46, 47.

depressa, 48.

Diesingii, 46.

dilatata, 48.

gracilis, 48.

- laticollis, 48.

VERMICULARIS, 15.

PARAMECIUM, 14.
PASSALUS, 14, 18, 27, 39, 51.

— CORNUTUS, 17, 18, 20, 22, 27, 28, 34,

35, 38, 39, 40, 41, 45, 51, 52.
PEDICULUS CAPITIS, 16.

TABESCENTIUM, 16.

VESTIMENTI, 16.

PENTASTOMUM CONSTRICTUM, 15.
PHTHIRIUS INGUINALIS, 16.
POLYDESMUS, 51.

GRANULATUS, 21, 30, 32.

- VIRGINIENSIS, 21, 29, 30, 32, 34,

36, 48.

PROTOCOCCUS NIVALIS, 8.
PULEX IRRITANS, 16.

PULEX PENETUANS, 16.
IlHUS VERNIX, 15.

SARCINA VENTRICULI, 16, 50.
SARCOPTES SCABIEI, 10.
SCARABEUS RELICTUS, 48.
SCOLOPENDRA, 21.
SPIROPTERA HOMINIS, 15.
SPH^ERIA, 53.
STREPTOSTOMUM, 27, 45, 49.

- AGILE, 19, 21, 27, 34, 36, 41,
45, 47.

GRACILE, 41, 46, 47.

STRONOYLUS GIGAS, 15.
STYLARIA FOSSULARIS, 10.
T^ENIA NANA, 15.

SOLIUM, 15.

TETRASTOMUM RENALE, 15.

Thelastonia dilatatum, 48.

TUELASTOMUM, 27, 46, 49.

APPENDICULATUM, 41, 47, 49.

- ATTENUATDM, 19, 21, 27, 34, 36,

41, 40.

• BREVICATJDATDM, 48, 49.

• DEJ'RESSUM, 48.
GRACILE, 48.

• LABIATUM, 32, 46, 47.

• LATICOLLE, 48.
ROBUSTUM, 48.

TRICHINA SPIRALIS, 15.
TRICOCEPHALUS DISPAR, 15.
TORULA, 16, 50.
VIBRIO, 10, 14, 41.

LINEOLA, 14.

VOLVOX, 14.
VORTICELLA, 14.

REFERENCES TO THE PLATES AND FIGURES.

PLATE I.

Fig. 1. Numerous tballi of Enterobryus eleyans, growing from a portion of mucous membrane of the
ventriculus of Julus munjinntiis. The breadth of the thalli, in the drawing, is greater than the relation of
their length.

a. Mucous membrane, covered with hexahedral epithelial cells.

l>. Primary cells of Enterobryus, filled with granules and globules.

c. Spiral turn performed by the thallus of Enterobryus eleijans in its course of growth.

d. Extremity of a primary cell filled with granular matter.

e. Secondary cells, usually filled with granular matter.

/. One of the secondary cells burst, with an escape of the mixed liquid and granular contents.

g. Arthromitus, a frequent parasitic algoid plant upon Enterobryus.

h. Pedicle of attachment of Enterobryus.

i. A thallus in outline, terminated by a single secondary cell.

Fig. 2. Thalli of Enterobryus attenuates, growing from a shred of basement-membrane, from the ventri-
culus of Passalws cornutm, magnified about twenty diameters.

Fig. 3. Five thalli of Enterobryus attenuatus, very highly magnified.

a. Basement-membrane of the mucous membrane of the ventriculus of Passalus cornutus.

b. Primary cells, filled with the characteristic contents of liquid, granules, and globules.

c. Pedicle.

d. A few filaments of Arthromitus, parasitic upon the Enterobryus.

Fig. 4. Four thalli of Enterobryus spiralis, growing from a portion of mucous membrane, from the ven-
triculus of Julus pusillus.

a. Hexahedral epithelia of the mucous membrane.

b. Thalli of Enterobryus, exhibiting the spiral arrangement and internal structure.

c. Primary cell.

d. Secondary cells.

e. Pedicle of attachment.

PLATE II.

Fig. 1. Numerous thalli of Enterobryus elegans, growing from a portion of mucous membrane of the
ventriculus of Julus marginatus.

a. Outline of the portion of mucous membrane.

b. Cylindrical epithelial cells of the mucous membrane.

c. Young thalli of Enterobryus, filled with the characteristic contents of liquid, globules, and a rela-

tively small quantity of granules.

d. Pedicle of attachment.

e. Masses of parasitic, granule-filamentous, phytoid matter, growing upon the mucous membrane.

f. The same kind of matter, growing upon the Enterobryus.

58 REFERENCES TO THE PLATES AND FIGURES. II.

g. Cladopliytum, parasitic upon the granule-filamentous matter.
h. Cladophytum, parasitic upon the Enterobryus.

i. Bunches of Arthromitus critfutus, growing in similar positions as the (.'ludojiliytum.
Fig. 2. Portion of the mucous membrane of the lower extremity of the large intestine of Julus manj inn-
tut, with very numerous young thalli of Enterobryus eleyant.
a. Mucous membrane in outline.
I. Epithelia.

c. Young thalli of Enterdbryus, in outline.

d. Two thalli, with granular contents and a very few globules.

Fig. 3. A single young thallus of Enterobryus ekgans, from the same position as Fig. '2, but more
magnified, so as to exhibit the contents.

a. The primary cell, with granular contents and a few globules.

b. The pedicle.

Fig. 4. A single individual of Enterobryus elegant, from the ventriculus of Julus manjinalus, artificially
twisted, exhibiting well the appearance of the interior contents.

a. The primary cell.

b. Its watch-crystal like termination.

c. The pedicle of attachment.

PLATE III.

Exhibits the structure of Enterobryus.

Fig. 1. Distal portion of a primary cell, with an unusually short attached secondary cell of E. elegans.

a. The portion of the primary cell filled with granules and globules.

b. A secondary cell, filled with granules. The distal extremity of this cell is abruptly terminated,

and the cell-membrane rises like the crystal of a watch from its dial.

Fig. 2. Central portion of a primary cell distended with globules. A few very minute granules are
visible.

Fig. 3. Proximal or attached portion of a primary cell.

a. Portion of the primary cell; its lower end slightly dilated, filled with globules and granules.

b. Portion of the pedicle.

Fig. 4. Dilated distal extremity of a primary cell, filled with globules; the latter, in the upper portion,
polyhedral from pressure.

Fig. 5. Central portion of the same cell containing granules and globules.
Fig. 6. Proximal portion of the same thallus.

a. Portion of the principal cell filled with granules and globules.

b. The pedicle.

c. Its expanded basis of attachment.

Fig. 7. Distal portion of a primary cell, filled with granules and globules, its upper end terminating
abruptly, with the cell-membrane rising like the crystal of a watch.
Fig. 8. Central portion of the same thallus, filled with granules and very large globules.
Fig. 9. Proximal portion of the same thallus.

a. Portion of the primary cell, filled with granules mixed with a few globules.

b. The pedicle of attachment, with four transverse contortions.

c. Its expanded base of attachment.

Fig. 10. Middle portion of a primary cell, very highly magnified, containing globules and granules.
Fig. 11. Proximal portion of the same individual as the last.

a. Portion of the primary cell, with globules and granules.

b. The pedicle, cut off below.

Fig. 12. Distal portion of a primary cell, clavate in form, filled with granules and globules, and having
its summit crowned with a profuse bunch of Arthromitus.

Fig. 13. Distal extremity of a primary cell of Enterobryus elegant, distended with a single row of large
globules.

II. REFERENCES TO THE PLATES AND FIGURES. 59

Fig. 14. Do. clavate in form, distended with large polyhedral globules.

Fig. 15. Distal extremity of a thallus of Enteroiryns atlcnnatas, with a short secondary cell.

a. Portion of the primary cell, filled with protoplasma, granules, and a few globules.

I. Secondary cell, burst at its upper extremity, and allowing globules of the protoplasma and granules

to escape.
Fig. 16. Distal extremity of an individual with a longer secondary cell.

a. Portion of the primary cell, with granules and a few globules.

b. Secondary cell filled with protoplasma, containing a few scattering granules.

Figs. 15 and 16 are representations of the only two instances of secondary cells which I ever observed
in Enterobryus attenvatus.

Fig. 17 represents the distal portion of a number of individuals of Enterobryus attcnuatua, exhibiting
the variations of the interior structure.

a. Distended with globules, varying in size in different individuals, but very uniform in the same indi-

vidual.

b. Filled with granules and globules irregular in size.

c. Outline of a portion of the primary cell.

d. Thickening of the cell-wall around the margin of the free extremity.

PLATE IV.

Fig. 1. A dead thallus of Enterobryus cleijans.

a. The pedicle.

b. The primary cell.

c. The contracted or shrunken primordial utricle.

d. Oil-like globules.

e. Branches of Cladopliytum.

Fig. 2. Distal extremity of a thallus, with the contents shrunken from the application of acetic acid.
Fig. 3. Spores? of Enterobryus elegant.
Figs. 4—17. Young thalli of Enterobryus eleyans.
Fig. 4. Very young condition : Length TJVo inch-
es. Point of attachment.
Figs. 5, 6. Further advanced : Length ?iff inch.

a. Young primary cell.

b. Pedicle.

Fig. 7. Young thallus constricted at the middle: Length 5-|j inch; breadth -j^j inch.
Fig. 8. Young thallus: Length j-J-j- inch; breadth T?fV<y incn-

a. Pedicle.

Fig. 9. Do. constricted at the lower portion of the primary cell, which is filled with protoplasma, granules,
and a few globules : Length T J5 inch.

Fig. 10. Do. curved, clavate, distended with globules : Length Ti5 inch.

Fig. 11. Do. same form as last: Length jL inch.

Fig. 12. Do. 7'j inch long.

Fig. 13. Do. straight, clavate, distended with globules : Length T|T inch.

Fig. 14. Do. long, straight, and clavate : Length Jv inch.

Fig. 15. Do. constricted at its upper third: Length ?L inch.

a. Pedicle.

b. Epithelial cells of the mucous membrane.

Fig. 16. Three young thalli growing from a portidn of mucous membrane, from a young Jului margina-
tus, one inch long.

a. Primary cell, filled with globules : Length y^v inch.

b. Do. clavate in form : Length 5|5 inch.

c. Do. overgrown with Arthromitus : Length Ti5 inch.

d. Cladiifliytum.

60 REFERENCES TO THE PLATES AND FIGURES. II.

e. Basement-membrane.

f. Epithelial cells.

Fig. 17. Do. geniculate, T^g- inch long.

Fig. 18. Distal portion of an ultimate secondary cell of Enteroliryiis dcyans, filled with granules and a
few globules, and having a tuft of Cladophytum growing from the summit.

Fig. 19. Proximal portion of the ultimate cell (a), and distal portion of the penultimate cell (6), of the
same individual as Fig. 18, filled with granules.

Fig. 20. Proximal portion of the penultimate cell (a), filled with granules, and distal portion of the pri-
mary cell (It), filled with granules and globules.

Fig. 21. Distal portion of an ultimate cell, filled with granules.

Fig. 22. Proximal portion of an ultimate cell, filled with granules (a), and distal portion of the penulti-
mate cell, filled with globules and granules (i).

c. Point of division of the two secondary cells.

Fig. 23. Proximal portion of the penultimate cell (a), and distal portion of the primary cell (i), filled
with granules and globules.

c. Line of separation of the primary from the secondary cells.
Fig. 24. Distal extremity of a secondary cell, filled with granules.

Fig. 25. Proximal extremity of the same cell, filled with granules (a), and distal portion of the primary
cell, filled with granules and a few globules (6).

c. Line of separation between the primary and secondary cell.

Fig. 26. A young thallus of Enterobryut attcnuatus, having an abnormal bud-like prominence at the
attached extremity of the primary cell. Large globules distend its upper half; small ones its sigmoid
'flexure, and protoplasrna fills the attached end and the bud. Length T'f of an inch.
', a. Primary cell.
b. Bud.
'c. Pedicle.

Fig. 27. A bunch of Enterobryus attenuatus, in which the primary cells are of very nearly uniform
diameter throughout, growing from a portion of basement-membrane. Length 1 line.

a. Principal cells, filled with globules, granules, and protoplasma ; the lower portions, excepting one, in

outline.

b. An individual, in which two principal cells grew from one pedicle. The only instance of the kind I

ever met with.

c. Pedicle.

d. Cladophytum.

e. Basement-membrane.

Fig. 28. Large bunch of Enterobryus eleyans, growing from a portion of mucous membrane.

a. Primary cells.

b. Penultimate secondary cell.

c. Ultimate secondary cell.

d. Pedicle of attachment.

e. Thallus in outline.

f. Bunches of CladopTiytum comatum.

g. Basement-membrane.
h. Epithelial surface.

PLATE V.

Figs. 1, 2. Secondary cells of Eccrina longa. All were filled with granular matter.

Fig. 1. a. A distal extremity of the primary cell, filled with granules and globules.

b. Outlines of secondary cells.

c. Secondary cell, filled with granules.
Fig. 2. a. Outlines of secondary cells.

b. Secondary cells, filled with granules-

II. REFERENCES TO THE PLATES AND FIGURES. 61

c. Thickening of the cell- wall at the place of division of the secondary cells.

Fig. 3. a. Distal portion of the primary cell of Eccrina longa, filled with granules and globules.

b. First secondary cell, filled with granules.

c. Outline of second secondary cell.

d. Arthromilus growing from Eccrina.

e. Its nucleus of attachment.

f. A tuft of Cladophytum.

g. Its nucleus of attachment.

Fig. 4. Terminal secondary cells of the same thallus as Fig. 3.

a. Filled with granules.

b. In outline.

Fig. 5. Secondary cells of Eccrina longa.

a. In outline.

b. Filled with granules.

c. Detached cells, which appear to adhere by one end to the sides of the parent thallus.
Fig. 6. Three detached secondary cells.

a. Filled with globules and granules.

b. In outline.

Fig. 7. Young thallus of Eccrina longa distended with globules; its upper part considerably dilated.
Figs. 8—13. Different forms assumed by the young of Eccrina, longa.

Fig. 8. 5}T inch long; 9, Ti5 inch; 10, -jiT inch; 11, ^^ inch; 12, 5ij inch; 13, more highly
magnified, yi^ inch.

Fig. 14. Arthromilus cristatus, from the large intestine of Julus marginatus.

a. Nucleus of origin.

b. Mucous membrane.

c. Consolidated articuli.

d. Spores.

e. Cladopliytum.

Fig. 15. Portion of another individual, more highly magnified.

a. Developing sporules.

b. Ripe sporules.

PLATE VI.

Fig. 1. An individual of Ascaris infeela, which had a large number of thalli of Entcrobryus clcgans
growing upon it.

a. Buccal organ.

b. Gizzard.

c. Intestine.

d. Rectum.

e. Anus.

f. Ovary.

g. Generative aperture.

h. Bunches of Arihromitus growing upon the thalli of Enterobryut.
Fig. 2. Anterior portion of the body of Ascaris infecta, with three thalli of E. elegans growing upon it.

a. Lobes of the mouth.

b. Buccal organ.

c. Gizzard.

d. Commencement of intestine.

e. Ganglia.

f. Primary cells of Enterobryus, filled with granules and globules, and having very numerous bunches

of Arihromitus growing upon them.

g. Pedicle of attachment.
9

62 REFERENCES TO THE PLATES AND FIGURES. II.

Fig. 3. Portion of a thallus, with numerous bunches of Arthromitus cristatus growing upon it.
Fig. 4. Middle portion of the body of Thdastomum attenuatum, with two thalli of Entvrulryus growing
from it.

a. Intestine; the spots represent its epithelial cells.

b. Oviduct.

c. Vagina.

d. Generative aperture.
f. Tegumeutary glands.
f. Enterobryus.

y. Pedicle.
h. Arthromitus.'

i. Bunch of Arthromitus growing from the generative aperture.
Fig. 5. Posterior portion of the body of Streptostomum agile,
a. Annuli of the body.
I. Tail, cut off below.

c. Posterior extremity of the intestine, with the hexahedral epithelial cells visible.

d. Rectum.

e. Anus.

f. Bundles of muscular fibres.

g. Portion of the oviduct containing an ovum.
h. Enterobryus elegans.

i. Bunches of Arthromilus cristatus.
Fig. 6. Side view of the posterior extremity of Ascaris in/ecta.

a. Portion of the intestine.

b. Rectum.

c. Anus.

d. Portion of Enterobryus elegans, with a very long pedicle of attachment («).
Fig. 7. Posterior view of the posterior extremity of Ascaris infecta.

a. Intestine.

b. Rectum.

c. Young thallus of Enterobryus, with a very long pedicle (<7), growing from the tail.

e. Arthromitus cristatus.

f. Cladophytum comatum.

Fig. 8. Alimentary canal of Passalus cornutus.

a. Proventriculus.

b. Ventriculus.

c. Intestine.

Fig. 9. Ventriculus of Passalus.

a. Commencement.

b. Caecal pouch opening into the ventriculus.

Fig. 10. Inferior portion of the ventriculus laid open.

a. The mouths of the sacculi.

b. The longitudinal folds.

c. The transverse folds.

d. V-shaped corneous plates.

e. Commencement of the fecal intestine.

II. KEFERENCES TO THE PLATES AND FIGURES. 63

PLATE VII.

Fig. 1. Anterior extremity of Thelastomum attenuatum.

a. Buccal organ.

b. Gizzard.

c. Commencement of the intestine.

d. Nervous ganglia.

e. Tegumentary follicle ; respiratory?

f. Tegumentary gland..

Fig. 2. Anterior extremity of Streptostomum agile,
a. Buccal organ.
l>. Gizzard.

c. Commencement of the intestine.

d. Portion of the anterior ovary.

e. Follicle ; respiratory ?

Fig. 3. Anterior portion of the body of Thelastomum appendiculatum.
a. Buccal organ.
It. Gizzard.

c. Intestine.

d. Diverticulum of the intestine.

e. Portion of the anterior ovary.

Fig. 4. Ovum of Thelaslomum appendiculatum.

Fig. 5. Group of Ascaris infecta, adhering by their mouths to a shred of epithelium, from the ventriculus
of Julus marginatus.

a. Male.

b. Female. .
Fig. 6. Outline of Streptostomum gracile.

Fig. 7. Anterior portion of the body of Streptostomum gracile.

a. Buccal organ.

b. Gizzard.

c. Commencement of the intestine.

d. Portion of the anterior ovary.

e. Phytoid filaments growing from the integument.
Fig. 8. Anterior extremity of Hystriijnalluis riyidus.

a. Papilla of the mouth.

b. Buccal organ.

c. Spinous appendages.

Fig. 9. Anterior extremity of Ilystrignathus rigidus.

a. Buccal organ.

b. Gizzard.

c. Commencement of the intestine.

Fig. 10. Posterior extremity of Hystrignaihus riyidus.

a. Posterior portion of intestine.

b. Rectum.

^

c. Anus.

d. Portion of the posterior ovary.

Fig. 11. Position of copulation of Ascaris infecta.

a. Male.

b. Female.

Fig. 12. Strqrtostomum agile, with Enterobryus eleyans and Arthromitus cristatus growing upon it.
a. Buccal organ.

64 REFERENCES TO THE PLATES AND FIGURES. II.

b. Gizzard.

c. Intestine.

d. Oviduct filled with ripe ova.

e. Rectum.

f. Anus.

g. Tail.

h. Enterobryus elegans.
i. Arthromilus cristatus.
Fig. 18. Anterior extremity of Thdastomum labiatum.

a. The lobed lip.

b. The buccal organ.

Fig. 14. Portion of the female generative apparatus of Ascaris infecta.

a. Ovary.

b. Pyriform commencement of the oviduct.

c. Mass of ripe ova, viewed by reflected light.

d. Termination of the anterior oviduct, in outline.

e. Uterus, with an ovum at its termination, viewed by transmitted light.
/. Spermatheca.

g. Vagina.

A. Generative aperture.

Fig. 15. Tail of Streptostomum agile, with a growing thallus of Entcrobryus eleijans («).
Fig. 16. Portion of the body of the male of Ascaris infecta.

a. Intestine.

b. Testicle.

Fig. 17. Posterior extremity of the male of A. infecta.

a. Intestine.

b. Testicle.

c. Penis.

Fig. 18. Spennatophori of A. infecta.

Fig. 19. One of the spiculae of the penis of A. infecta.

Fig. 20. Outline of the posterior extremity of A. infecta, exhibiting the ventral tubercles.

Fig. 21. Alimentary canal of Julus maryinatus, magnified two diameters.

a. Conglomerated salivary glands.

b. Tubular salivary glands, at their terminal portion.

c. (Esophagus.

d. Pr^ventriculus.

e. Biliary tubes.
/ Fatty band.
g. Ventriculua.

h. Large intestine.

t. Rectum.

Fig. 22. Young of Ascaris infecta.
Fig. 23. Young of Thelastomum attenuatum

II. REFERENCES TO THE PLATES AND FIGURES. 65

PLATE VIII.

Fig. 1. A transverse fold of the ventriculus of Passalus cornutus, with numerous hair-like appendages
covered with granulo-filamentous phytoid matter, and bunches of dadophytvm and Corynodadus.

a. Mucous membrane.

b. Hairs.

c. Phytoid substance.

d. Cladophytum coma/urn,

e. Corynodadus radiatus.

f. Arthromitus cristatus.

Fig. 2. Portion of the mucous membrane of the ventriculus of Jidus marginatus, with patches of granulo-
phytoid matter growing upon it.

a. Patches of granulo-phytoid matter.

b. Harder nuclei of phytoid matter.

c. Bunches of Cladophytimi comalum.

d. Arthromitus cristatus.

e. Epithelial surface.

f. Basement-membrane.

Fig. 3. Portion of Enterobryus eleyans, with two large bunches of Arthromitus cristatus, and a tuft of
Cladophytum.

Fig. 4. Portion of Enterobryus elegans, overgrown with profuse bunches of Arlhromitus cristatus.

Fig. 5. Summit of a hair-like appendage, from which grow numerous filaments of Arthromitus and other
finer phytoid filaments, from the ventriculus of Passalws cornutus,

Fig. 6. Summit of a primary cell of Enterobryus elegans, from which grows a bunch of Cladophylum
comatum.

Fig. 7. Two branches of Cladophytum, exhibiting minute ramuli.

Fig. 8. Bunch of Cladophytum comalum, and several long filaments of Arthromilus growing from a
portion of the mucous membrane of the ventriculus of Julus maryinatus.

PLATE IX.

Fig. 1. Represents a portion of the inner surface of the ventriculus of Passalus cornutus, with its numerous
hair-like appendages enveloped in a parasitic, granulo-filamentous, phytoid substance.

a. Light shading, representing the bottom of the sacculi of the ventriculus, furnished with short hairs.

b. Broad transverse folds of the mucous membrane, between the sacculi.

c. d. Longitudinal folds separating the sacculi, and presenting on each side, between the position of

the transverse folds, a column of closely-set, simple, bidentate, and tridentate corneous spines.

e. Long hair-like appendages, which border the ventricular sacculi and become the nuclei of large

masses of growing phytoid matter.

f. Short hairs, everywhere studding the mucous membrane, and also enveloped with phytoid matter.
Fig. 2. Portion of a transverse fold of mucous membrane, from between the ventricular sacculi of

Passalus cornutus, with its hair-like appendages enveloped in phytoid matter exhibited of the natural colors.

a. Mucous membrane.

b. Hair-like appendages.

c. Granulo-filamentous phytoid matter.

d. Bunches of Cladophytum.

e. Bunches of Corynodadus.

66 REFERENCES TO THE PLATES AND FIGURES. H.

PLATE X.

Fig. 1. Corynocladus radiatus, from the ventriculus of Passalus cornutus.

a. Trunk.

b. Clavate branches.

c. Investment of granular phytoid matter; sporular ?

d. Arthromitous filaments.

Fig. 2. Extremity of a branch of Corynocladus, very highly magnified, exhibiting the manner in which
adhering matter appears dimly shaded, consisting, probably, of spores of the plant.

Fig. 3. Three filaments of a doubtful nature, whether vegetable or part of the animal structure of the
ventriculus of Passalus cornutus, formerly called, by me, Cryptodesma tennis.

Fig. 4. Polyspore ? from the ventriculus of Polydesmus granulatus, found mixed with the food.

Fig. 5. Inferior portion of another individual from the same situation.

Figs. 6, 7. Polyspores? found mixed with the food in the ventriculus of Passalus cornutus.

Fig. 8. Ergot, Ergotaetia abortifaciens ? found in the proventriculus of Aclieta nigra.

Figs. 9—12. In dead individuals of Julus marginatus, within the ventriculus and large intestine, I
frequently observed a fungus in the form of small, white, translucent, compressed, spheroidal bodies, growing
upon the mucous membrane, or upon dead filaments of Enterobryus lying upon the mucous membrane. The
centre of these bodies was depressed, and the surface covered with fine longitudinal striae, intersected by
short transverse striae. By reflected light, they resembled minute bleached shells of Echini. They measured
from the 7555 to tne IFO °^ an 'ncn broad. Upon pressure, they burst or dehisced into several leaf-like
finely-striated lobes, and exuded a clear but faintly granular liquid.

Fig. 9. Two of the fungous bodies, just described, viewed by reflected light.

Fig. 10. A group of the same bodies growing upon a filament of Enterobryus, also viewed by reflected
light.

Fig. 11. One of these bodies viewed by transmitted light.

Fig. 12. One of these bodies burst into six leaf-like lobes from pressure.

Fig. 13. A polyspore? from the large intestine of Julus marginatus.

Figs. 14-21. Fungous sporuli, in various stages of development, found in the fecal contents of the large
intestine of Salamandra erythronota, S. salmonea, Triton niger, etc. They are probably found in the cloaca
of all the Salamanders.

Fig. 14. Much more highly magnified than the others.

Figs. 18, 20, 21. In outline.

Figs. 14-17, 19.

a. Granular matter.

b. Transparent liquid.

Fig. 22. Fungus mycelium, found growing in the cloaca of Triton niger.

a. Colorless liquid.

b. Granular contents.

c. Nuclei.

d. Phytoid filaments, at the basis of which was a quantity of adherent granular matter.
The small isolated lines represent a species of Bacterium, which existed in vast numbers.

Fig. 23. Fungus developed from the spores of Figs. 14-21, and the mycelium, Fig. 22, upon the dung
of Salamanders when exposed to the external air. A species of Torula, or perhaps J3riarea?

a. Spores.

b. Spores in outline.

c. Receptacle.

d. Mycelium.

Fig. 24. Portion of mycelium, with contained spores, of the same fungus as Fig. 23.

a. Spore.

b. Spore in outline,
f. Mycelium.

II. REFERENCES TO THE PLATES AND FIGURES. 67

d. Shrivelled portion of mycelium.
Fig. 25. Spores found upon the dung of Salamanders.

Fig 20. Fungoid body found within the ventriculus of a hybernating larva of Arctia Isabella. Proba-
bly the tissue of some fungus, which may have served the animal as food.
Figs. 27, 28. Fungus mycelium, from the vagina of Cicada septendedm.
Fig. 29. Spores from the same situation as Figs. 27, 28.

PUBLISHED BY THE SMITHSONIAN INSTITUTION,

WASHINGTON, D. C.

APRII, 1853.

Plate I.

Plate II.

Plate III.

Plate IV.

Plate V.

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Plate V

Plate Vlll.

Plate. IX.

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