PREFACE. ]X 



assistance rendered to the present volume by those friends who 

 have acted either as editors or revisers. If the result meet with 

 approval, to them be the honour ; if otherwise, I am prepared to 

 share the blame, for nothing whatever has been arranged without 

 my concurrence, or written that has not passed under my revision. 

 But in truth the book has to me associations more grave than any 

 connected merely with literary praise or censure. It speaks to 

 me of four lamented friends, Thompson, Forbes,* Johnston,t and 

 Garrett ; J they laboured in very different spheres, yet were all 

 actuated by the same object, 



" to know 

 The works of God, thereby to glorify 

 The great Workmaster." 



In little more than three years they passed away. They were 

 endeared to me by personal intimacy or unreserved correspond- 

 ence. Their labours are connected in different ways with the 

 present volume, and in it their names are of frequent occurrence. 

 What wonder then that a voice of solemn admonition comes to 

 me from its pages, and breathes into my ear the words of the 

 Psalmist, " The days of man are but as grass, for he flourisheth as 

 a flower of the field ; for as soon as the wind goeth over it, it is 

 gone, and the place thereof shall know it no more ! " 



EGBERT PATTEESOX. 



Belfast, 2Wh 3farch, 1856, 



* Professor Edward Forbes died at Edinburgh, 18th Nov., 1854. A sketch of 

 his life and labours, from the pen of his friend and colleague. Professor Balfour, 

 is given in the Annals of Natural History for January, 1855. It concludes most 

 appropriately by quoting the statements made regarding him by four men of 

 eminence, viz., an anatomist, a botanist, a geologist, and a zoologist, who well 

 knew his merits. 



t Dr. George Johnston died at BerAvick-on-Tweed, 30th July, 1855, a toAMi 

 to which his labours have given a scientific celebrity. An enumeration of his 

 principal writings appeared in the Athenaeum and in "the Literary Gazette on the 

 ensuing Saturday (Aug. 4), and a Biographical Sketch in the Edinburgh Medi- 

 cal Journal of September, 1855. 



J Mr. James R. Garrett died of fever on the 2nd of April, 1855, in the thirty- 

 eighth year of his age. In the Dublin Natural History Review for July, 1855, 

 there appeared a notice of the event, in which justice is done to his attainments 

 as a naturalist, his " imassuming manners, kindly disposition, and simple yet 

 refined tastes." 



