126 
Transactions of the Royal Microscopical Society. 
XX. Minute Structure of a peculiar Combustible Material from the Coal 
Measures of Torbane Hill — “ Boghead Cannel Coal.” 
Observations undertaken chiefly in reference to a trial in Edin- 
burgh, “ having for its object the determination whether the Torbane 
Hill material should be called a coal or not, and whether it should 
be included in the missive of agreement for a lease, and let as 
coal.'’ “ With four of these classes of scientific witnesses ” (geolo- 
gists, chemists, &c., &c.) “ I have no immediate concern, and will 
therefore leave them to settle their own differences ; but not so 
with the microscopists, with many of whom my opinions are 
entirely at variance.” The course of the trial was much enlivened 
by some remarks of the judge, who represented the two principal 
witnesses (the Professor and Mr. Bowerbank), as not “ conversant 
or skilful in fossil plants,” and informed the jury that the Micro- 
scopical Society of London “is a learned body who make it their 
object to pry into all things.” Bead December, 1853. No. 6, 
p. 34. 
XXI. Structure of the White Filamentous Substance surrounding the 
so-called Mealy Bug (Cocas vitis ) of the Vine. Bead January, 
1857. No. 21, p. 1. 
And now, Mr. President, passing to the anatomy of ants, I 
had hoped to have been able to give, not of course a complete, but 
at least a more detailed account of their structure than 1 am now 
able to lay before you. The pressure, however, of other duties, and 
the complexity of organization of these wonderful insects, have pre- 
vented me from executing the task, which I had set to myself, so 
thoroughly as I could have wished. I must therefore confine 
myself within narrower limits, and must express my regret that 
I cannot deal with the subject in a more satisfactory manner, 
though I venture to hope that some of the points which I shall 
have to bring before you are not altogether without interest. 
The body of ants consists of three principal parts — the head, 
the tliorax, and the abdomen. 
The head is arched above and more or less flattened on the 
under side. On the upper surface are placed the eyes and the 
antennae, in front is the mouth, surrounded by the labium or upper 
lip, the first pair of jaws or mandibles, the second pair of jaws or 
maxillae, and the lower jaw or labium. At the posterior end is the 
occipital orifice, through which the oesophagus, the nervous system, 
the tracheae, the duct of the large salivary glands, &c., pass from 
the head into the thorax. 
On the upper side of the mouth, between the mandibles and the 
antennae, and forming the front edge of the upper side of the head, is 
the clypeus (Plate CXCII., Fig. 1, c). It is more or less distinctly 
separated from the rest of the head by a furrow corresponding 
with an internal inter-antennal ridge, shown in section in Plate 
CLXXXIX., Fig. 6. The clypeus is sometimes divided by a 
median ridge. It varies considerably in form in different species, 
but is generally either quadrangular, or triangular with the broader 
