摘要:

1. The sixth abdominal ganglion (6 A.G.) of the lobsterHomarus gammarus(L.) innervates the rectum via the paired posterior intestinal nerves (P.I.N.’s) and the paired anal nerves. The anterior branches of the P.I.N.’s supply the anterior hindgut, the main faecal expulsion region, whilst the posterior branches (P.I.N.p.’s) supply the posterior region and the 5 extrinsic radial muscle groups around the anus.

ISSN:0091-181X    

DOI:10.1080/10236247209386887

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

1. Two types of motor activity pass from the sixth abdominal ganglion (6 A.G.) via the posterior intestinal nerves (P.I.N.’s) to the hindgut ofHomarus. These have been designated unitary or non‐repetitive and bursting or repetitive activity. They are not entirely exclusive of one another.

ISSN:0091-181X    

DOI:10.1080/10236247209386888

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

Spacing between individuals in populations ofHarmothoë imbricatahas been investigated both on the shore and in the laboratory. Males tend to occur closer together than females, and the mean male‐male individual distance measured was less than the mean distance between females; male—female distances for immature worms were intermediate. When worms mature they pair: the male mounts the female and lies across her dorsal surface. There is evidence that after spawning the members of a pair separate. Contact responses between worms have been investigated in the laboratory. Most encounters between immature worms lead to separation, as a result of one or both worms moving rapidly away from the other or fighting; females show more marked avoidance behaviour than males. The majority of male‐male and female‐female encounters between mature worms also lead to separation but in male‐female encounters the male usually mounts the female. A male which has mounted a female becomes highly aggressive and will attack intruding males but not females.

ISSN:0091-181X    

DOI:10.1080/10236247209386889

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

If the optic glands are removed from mature male octopuses, the weight of the testis and its ducts decline. Spermatophore production eventually ceases after five or six weeks. The effect of the operation is most marked in the case of large animals. If the glands are activated by removing the source of their nerve supply in the subpedunculate lobe of the suprapesophageal brain, testis and duct enlargement follows enlargement of the glands themselves ; the number of spermatophores found in the male ducts doubles within a month of the operation. Castration of the animals is not followed by a change in the weight of the male ducts, indicating that the optic gland secretion affects the state of the ducts directly rather than through the testis.Octopus vulgarisCuvier andO. cyaneaGray were used in the experiments.

ISSN:0091-181X    

DOI:10.1080/10236247209386890

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

Models were presented to 102 specimens of the spider crabMicrophrys bicornutusto test the importance of several appendage and body postures, which occur during agonistic interactions. The double first ambulatory raise posture and the cheliped spread posture both elicited a significant number of agonistic responses. Multiple ambulatory raise postures and raised or lowered body postures did not elicit significantly different response spectra. Size and sex of test animals seemed to have little effect on their responses.

ISSN:0091-181X    

DOI:10.1080/10236247209386891

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

1. The structure of the sixth abdominal ganglion (6 A.G.) ofHomarushas been determined using light microscopy. The ganglionic cortex is divided into anterior and posterior ventral lobes. A pair of dorsal lobes arises from the posterior ventral lobe. Four pairs of commissures cross the ganglion and six pairs of nerves arise from it.

ISSN:0091-181X    

DOI:10.1080/10236247209386892

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

P. platycheleswas found to be euryhaline while the relatedP. longicornisproved to be stenohaline. Prior acclimation to 60 % s.w. improved survival in 40 % s.w. inP. platycheles. Salinity preference was demonstrated inP. platycheles, which could avoid low salinities and move along salinity gradients to do so; at high salinities the Weber‐Fechner “law” may operate for this crab as it could avoid high salinities but could not differentiate between two high salinities, separated by 3.4‰.P. platychelesdifferentiated between solutions on the basis of their total osmolarities, and the ability to do so was significantly impaired by removal of the antennules.P. longicornisexhibited no ability to distinguish between salinity levels.

ISSN:0091-181X    

DOI:10.1080/10236247209386893

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

The behaviour of theHarmothoëtrochophore changes with age, the larva being phototropic initially and later photonegative.

ISSN:0091-181X    

DOI:10.1080/10236247209386894

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

The mechanical arrangement of the PD organ ofCancerhas been studied and equations derived which relate its length to the articulation angle of the PD joint and to the angle which the receptor strand makes with the dactylopodite flexor tendon. These relationships are discussed in the light of the anatomy of the PD articulation.

ISSN:0091-181X    

DOI:10.1080/10236247209386895

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

ISSN:0091-181X    

DOI:10.1080/10236247209386896

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor