No. 1.] ACTINIARIA OF THE BAHAMAS. ie 3 
Although considerable contraction usually results from this 
process, and although the color is, as a rule, almost destroyed, 
yet I think the distortion is less than that resulting from most 
other methods, and there is the great advantage that the parts 
are preserved in a satisfactory manner for future histological 
study. Dissection is possible, owing to the absence of the 
excessive brittleness which results from the use of chromic 
acid, encrusting or attached calcareous particles are dissolved, 
and sectioni=g of entire small forms may be practised without 
the danger of ruining the knife, and, lastly, there is no un- 
pleasant precipitation of crystals as occurs from the use of 
corrosive sublimate when the subsequent washing has not been 
sufficiently prolonged. 
So far as I am aware, there exist no records of observations 
upon the Actiniaria of the Bahamas, although quite a number 
of forms have been described from others of the West Indian 
islands. Duchassaing and Michelotti (‘60 and ’66) have described 
many of the forms occurring in the Antilles; but in their ob- 
servations they took account only of external characteristics, 
and even with regard to these their descriptions are often so 
imperfect as to render it difficult to ascertain the true relation- 
ships of the forms under consideration. Lesueur (17) has also 
described several forms from the Antilles ; and, lastly, Ellis has 
mentioned and figured one or two specimens in a letter to the 
Earl of Hillsborough published in the Philosophical Transac- 
tions (67). 
Owing to the great confusion which exists in the synonomy 
and classification of the Actiniaria, notwithstanding Andres’ 
excellent work (83), it will be necessary to map out the exact 
limitations of the various groups and forms to be described 
here ; and in most cases an historical review of the synonomy 
will be required. 
Before concluding these introductory remarks I must ac- 
knowledge the obligation under which I rest to the officers of 
the Academy of Natural Sciences of Philadelphia, through 
whose courtesy and kindness I was permitted to make use of 
the magnificent library of that institution. Without this favor 
I should have been unable to unravel many of the tangled 
threads of synonomy which the investigations to be discussed 
in the following pages brought to my notice. 
