REPORT ON THE STOMATOPODA. . 3 



WhUe I have beeu able to show, from the study of the Challenger specimens, that 

 many of Claus's conclusions are incorrect, and that he referred some of the most familiar 

 larval types to the wrong adult genera, I feel that I could not have accomplished this 

 alone, and that, while my results are in many cases directly opposite to his conclu- 

 sions, my ability to reach and to prove them is due, in a very great degree, to the study 

 of his memoir-. The labour of tracing the history of the larvge has been so simplified 

 through the accurate illustrations and ample and minute descriptions which he has 

 furnished, that the investigator who follows him in this field has much of the difficulty 

 removed, and, while I feel that I leave the subject in a much more satisfactory condition 

 than that in which I found it, I also feel that I could not have made the same progress 

 without the aid of his memoir. 



The beautiful transparent, glass-like pelagic larvae of the Stomatopoda are familiar 

 to all naturalists who have had an opportunity to study pelagic life, and none of the 

 animals which are captured at the surface in the tow-net exceed them in interest to the 

 student, or in beauty and grace. Their perfect transparency, which allows the whole of 

 their complicated structure to be studied in the living animal, their great size and 

 rapacity, the graceful beauty of their constant and rapid movements, and the pro- 

 fundity of the morphological problems which they present for solution, cannot fail to 

 fascinate the naturalist. Unfortunately they are as difficult to study as they are 

 beautiful and interesting, and, notwithstanding their great abundance and variety, only 

 two or three of them have been traced to their adult form. 



Unlike most Malacostraca, the Stomatopods, instead of carrying their developing eo-o-s 

 about with them, deposit them in their deep and inaccessible burrows under the water, 

 where they are aerated by the currents of water produced by the abdominal feet of the 

 parent, which are so shaped as to form valves or paddles which exactly conform to the 

 outline of the cylindi-ical hole. The eggs quickly perish when depiived of this constant 

 current, and as it is very difficult to procure them at all, I know of no young Stomatopod 

 which has been reared from an egg outside the burrow or in an aquarium. The older 

 larvae are hardy, and they thrive in small aquaria and moult into the adult form, but 

 they are seldom found near the shore, and microscopic research is so difficult in mid ocean 

 that almost nothing has been accomplished in this way. The younger larvge are common 

 near the shore, but they seldom pass through a moult in confinement, and the only way 

 to trace the life-history of the Stomatopoda is therefore by the comparison of the series 

 of larvae which are collected in the ocean, and this is attended with peculiar difficulties, 

 for the number of larval forms which have been described is much greater than the 

 number of adults which are known, and many of them unquestionably belong to unknown 

 species, and possibly to unknown genera. 



The growth of the larvae is very slow, and the larval life long, and as they are as 

 independent and as much exposed to changes in their envii-onmeut, and to the struggle 



