THE HISTORY OF THIS WORK. 



AT a date between 1855 and 1860, Mr. Joshua Alder, 

 at the request of Dr. J. E. Gray, Keeper of the 

 Zoological Department of the British Museum, under- 

 took to prepare a ' Catalogue of British Tunicata.' 

 This Catalogue was to be published by the British 

 Museum as one of a series of works which included 

 Busk on the ' British Polyzoa,' Spence Bate on the 

 * Crustacea Amphipoda,' and George Johnston on 

 ' British Nonparasitic Worms.' Alder at once gave 

 his whole time to the preparation of this volume. In 

 1863 the work was done, the whole of the descriptive 

 portion neatly written out and ready for the printer, 

 while the Plates, which gave coloured illustrations of 

 the then known species, together with drawings of 

 portions of the branchial sac of many of the forms, 

 were completely finished, and only required engraving. 

 When, however, Alder wrote to Dr. Gray to inform 

 him that this was the case, he received a letter in 

 reply which expressed the deepest regret that the 

 Trustees (or the Government r) had withdrawn the 

 grant for the publication of these Catalogues, and that 

 therefore, unfortunately, he was imable to avail him- 

 self of Alder's valuable work.* 



The last of these Catalogues, that of Dr. Johnston, was not published 

 until 1865, but, as noted in the Preface, " the publication had been delayed 

 owing to the lamented death of Dr. Johnston," after which it was completed 

 by Dr. Baird. 



