Journal of Morphology

doi: 10.1002/jmor.1051520101pmid: N/A

Gaunt, Abbot S.; Gaunt, Sandra L. L.

doi: 10.1002/jmor.1051520102pmid: 870697

Records of electrical activity in the tracheal muscles of domestic chickens were obtained for a variety of ad libitum vocalizations. Primary attention was given to an analysis of events during the most complex call, crowing.

Meiss, Dennis E.; Norman, Richard S.

doi: 10.1002/jmor.1051520103pmid: 30241428

The skeletal structure of the stomachs of several decapod Crustacea is described in detail. The general organization of the ossicles is similar for all species and the homologies of the elements can be recognized despite large variations from group to group. The Reptantia are characterized by a complex ossicle organization while the Natantia, on the other hand, are characterized by a simple organization. The various types of ossicle organization found in the decapod stomach can be arranged in a series ranging from simple to complex. The Brachyura have the most complex ossicle system and the Penaeidea the most simplified. This graded series of complexity closely follows the evolution of the Decapoda.

Meiss, Dennis E.; Norman, Richard S.

doi: 10.1002/jmor.1051520104pmid: 30241434

The stomach musculature of several species of decapod Crustacea is described in detail. All species are sufficiently similar so that muscle homologies can be established. The Natantia have a simplified muscle system while the Reptantia are characterized by a more complex muscle system. Species can be arranged in a graded series of muscle system complexity which closely follows the evolution of the decapod Crustacea. The information presented here should provide the basis for consistent identification of the stomatogastric motor neurons throughout the decapod Crustacea.

Woollacott, Robert M.

doi: 10.1002/jmor.1051520105pmid: 30249075

The complex array of vestments which surrounds the ascidian oocyte indicates that spermatozoa of these urochordates may be highly modified to effect penetration through the egg‐envelopes and to achieve successful fusion with the female gamete. Examination of the spermatozoa of Ciona intestinalis reveals, however, that they lack an acrosomal vesicle and do not possess detectable amounts of actin. Furthermore, the spermatozoa do not undergo observable morphological alterations when exposed to ammoniated seawater, a treatment known to produce aggregation and an acrosome reaction in other organisms. Ciona spermatozoa do contain significant quantities of proteases. It is hypothesized that the localization of these enzymes may be related to the ridge‐like surface ornamentation which is observed as a component of the head region of Ciona spermatozoa.

Ruben, John A.

doi: 10.1002/jmor.1051520106pmid: 30249077

Dissection of the cervical and basicranial regions in three species of snakes indicates that compared to Crotalus viridis and Lichanura roseofusca, Masticophis flagellum possesses relatively high numbers of compound axial muscle insertions on the atlas‐axis and vertebrae numbers 3‐5. It is suggested that the condition in Masticophis facilitates its vertical‐neck‐horizontal‐head foraging posture and has allowed axial muscles inserting on the dorsocaudal braincase in this snake to generate vertical and lateral head movements more effectively.

Holmes, Robert

doi: 10.1002/jmor.1051520107pmid: 30253636

The osteology of the pectoral limb of small captorhinids is described and figured in detail. A cartilaginous sternum was present. The glenoid was not a simple sliding or rocking joint, as was previously supposed, but considerable rotation was also an integral part of the humeral movement. The structure of the elbow joint is such that when the lower arm was extended, its distal end swung forward and extended the anterior reach of the hand. When the lower arm was flexed, the posterior reach of the hand was extended. Articulated specimens allow a recontruction of the manus. There was no well developed wrist joint, but rather the manus, as a whole, was a flexible structure. A pisiform was present. Sesamoid bones were developed in the tendons of the palmaris communis profundus muscle.