. Beginners' Zoology . to swimmerets ? Do they likewise have the Y-shaped structure ? (Fig. ^^.^ If the swimmerets on the first abdominal segment are large, the specimen is a male. If they are small, it is a female. Which sex is shown in Fig. 82 . Fig. 86}Carapace. — The covering of the head chest (cephalothorax) is called the cara-pace. Has it free edges i The gills are on the sides of the body and are covered by the carapace (Fig. ^j). The projection in front is called the rostrum, meaning beak. Does the rostrum project beyond the eyes. There is a transverse groove across the cara-pace which

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. Beginners' Zoology . to swimmerets ? Do they likewise have the Y-shaped structure ? (Fig. ^^.^ If the swimmerets on the first abdominal segment are large, the specimen is a male. If they are small, it is a female. Which sex is shown in Fig. 82 . Fig. 86}Carapace. — The covering of the head chest (cephalothorax) is called the cara-pace. Has it free edges i The gills are on the sides of the body and are covered by the carapace (Fig. ^j). The projection in front is called the rostrum, meaning beak. Does the rostrum project beyond the eyes. There is a transverse groove across the cara-pace which maybe said to dividethe head from theabdomen. Wheredoes this groove end at the sides }Legs. — How many legs has thecrayfish? How many are providedwith large claws } Small claws }Is the outer claw hinged in eachof the large grasping pincers}The inner claw } Appendages for Taking Food. —If possible to watch a living cray-fish eating, notice whether it places the food directly into the mouth with the large claws. B

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