The President's Address. By Henry Woodward. 155 



The Crustacea, represented in past time by persistent forms suck as the 



Entomostraca — 



Ostracoda ...... Cambrian to recent. 



Phyllocariila ...... „ „ 



(Xiphosurn) Limulus .... Silurian to recent. 



The Arachnida. 



Scorpionidae (Scorpio) .... Silurian to present day. 



The Myriopoda ....... Coal-measures to recent. 



The Insecta. 



Neuroptera ...... Coal-measures to recent. 



Orthoptera ...... 



Thysaniua ...... „ „ 



Homoptem ...... ,, „ 



Of Newer Groups, 



The following groups which have appeared in newer geological time may 

 lie cited — 



The Bryozoa .... from Carbonifirous to recent. 



The Eclrinohlea, or " Sea-urchins " 



The Pteropoda (proper) 



The Gasteropoda 



The Decapoda 



The Isopoda, &c. 



And the great mass of living Insects, from the Secondary to recent. 



The Pange in time of the principal groups of the Invertebrata 

 is given in a diagram form on p. 156, showing the Persistent 

 groups (P.), the Extinct groups (E.), and the comparatively 

 Modern groups (M.). 



If we except such groups as the Crinoids, the Brachiopods, the 

 Nautilidre, the Xiphosura — which evidently attained their greatest 

 maximum in the past, and although still surviving are now but a 

 feeble folk — we shall notice that the modern Echinoids, Bryozoa, 

 Mollusca, Gasteropoda (Siphonostomata and Pulmonifera) ; the 

 higher Crustacea (Decapoda, Brachyura, and Macrura) the Isopoda, 

 Stomapoda, &c. ; and our modern Insects, are far in advance of 

 their " forbears " as regards development, and this is especially true 

 of all the higher forms of life. 



Just as in the Vegetable world our modern Flora (with its 

 wealth of Flowering plants) is far more highly organised, varied and 

 beautiful than in the past ages of the world, so is the associated 

 Fauna of to-day when contrasted with that of the past. 



But, it may be asked, what prospect is there of arriving at the 

 earliest known ancestor from which all these varied forms have 

 been derived ? What help does the geological record afford us ? 

 My duty, as your guide, is to inform you that our increased know- 

 ledge of the older rocks has not shown that we are nearer the 

 fulfilment of the young biologist's dream, and the secret of 

 Pandora's Box remains still undiscovered. We have not as yet 

 reached the beginning; of life. 



