162 Journal of the Mitchell Society [February 



and utterly negative the commonly accepted idea that the devil- 

 fishes, as the Mantid rays are commonly called, live on shell- 

 fish. Coles watched them fishing in small schools for minnows, 

 using their cephalic fins to form funnels for scooping the min- 

 nows into their wide mouths. On dissection he found only 

 small fishes in their stomachs. 



Coles captured 9 of these rays in 1910 and saw a school vari- 

 ously estimated to contain 30 to 50. Their favorite sport con- 

 sists in leaping into the air, and this of course makes it very 

 hard to estimate the number in a school. IS^one of these rays ex- 

 ceeded 5 feet in width. The color of the fresh specimens is 

 black but after death this changes to a dark blue. The com- 

 monly accepted idea is that the horns of the Mantids are mov- 

 able and that they are used to grasp objects and transfer these 

 to their mouths. Coles by experiment proved that this is not 

 true of Mobula. The horns have little if any movement but the 

 cephalic fins, which are ordinarily carried tightly wrapped 

 around the horns, may be distended and used as indicated 

 above. 



■Coles had the good fortune to see these rays in sexual union, 

 belly to belly, the female underneath on her back, her pectorals 

 curved upward closely embracing the pectorals of the male 

 which were also curved upward. Copulation lasted for some 

 time but was not continuous, being interrupted by separations 

 during which the fish leaped into the air or swam in graceful 

 curves. 



By an interesting coincidence. Coles first three captures of 

 this ray in 1911 were made on the same days as those in 1910, 

 viz., July 6, 7, and 8. On these days he took 7 specimens, 6 

 males and one female. ISTo others were then seen in the bight of 

 the Cape until the night of Aug. 3, when the fishermen reported 

 a leaping devil-fish on the eastern side of the Cape breakers. 

 Daylight found Coles on the spot where he saw one leap and a 

 school pass under his boat. He surrounded this school in 10- 

 foot water, and captured 7 specimens (1 male and 6 females) 

 while one escaped over the cork-line and 2 under the lead-line. 



Of the 14 specimens taken, Coles has retained 3 and has pre- 



