INTRODUCTION, 
In bringing my Monograph on the Asteroidea and Ophiuroidea. to a close a few- 
words of explanation appear to be necessary in order to avoid any misconception as 
to the cause that has occasioned delay in the completion of the work. 
When I had assembled for the first time all the materials I had collected for the 
volume I found, much to my regret, that the specimens were fewer and more frag- 
mentary than I anticipated, and that it was impossible to carry out the description of 
the families in a manner similar to the one I had adopted in the Echinoidea. I 
therefore determined to figure and describe all the species that I had collected and wait 
for the discovery of others in public and private collections which I had not at that 
period been able to inspect. The part containing the Asteroidea appeared in 1863, 
and the part on the Ophiuroidea in 1866. Since then I have made diligent search 
among all collections that were likely to contain Jurassic Echinoderms, and after many a 
hunt I have only succeeded in obtaining two additional species from these sources, and 
finding a much better specimen of an important Yorkshire species, Astrojpecten rectus, 
of which I have given a good figure. 
In the usual progress of discovery by waiting patiently for new things sometimes 
a few specimens are met with, and I am happy to say that my patience has been 
rewarded. Among the Goniasterid^ a very fine specimen of Stellaster was collected 
by my friend Samuel Sharp, Esq., E.G.S., from the ironstone beds of Inferior Oolite 
near Northampton, certainly one of the finest fossil Star-fishes which the Inferior Oolite 
has hitherto yielded up. An allied species was soon afterwards discovered in the 
" Calcaire a Entroques," a bed of the same age, at Macon (France). 
h- a 
